openssl/Configure

#! /usr/bin/env perl
# -*- mode: perl; -*-
# Copyright 2016-2020 The OpenSSL Project Authors. All Rights Reserved.
#
# Licensed under the OpenSSL license (the "License").  You may not use
# this file except in compliance with the License.  You can obtain a copy
# in the file LICENSE in the source distribution or at
# https://www.openssl.org/source/license.html

##  Configure -- OpenSSL source tree configuration script

use 5.10.0;
use strict;
use Config;
use FindBin;
use lib "$FindBin::Bin/util/perl";
use File::Basename;
use File::Spec::Functions qw/:DEFAULT abs2rel rel2abs/;
use File::Path qw/mkpath/;
use OpenSSL::Glob;

# see INSTALL for instructions.

my $orig_death_handler = $SIG{__DIE__};
$SIG{__DIE__} = \&death_handler;

my $usage="Usage: Configure [no-<cipher> ...] [enable-<cipher> ...] [-Dxxx] [-lxxx] [-Lxxx] [-fxxx] [-Kxxx] [no-hw-xxx|no-hw] [[no-]threads] [[no-]shared] [[no-]zlib|zlib-dynamic] [no-asm] [no-egd] [sctp] [386] [--prefix=DIR] [--openssldir=OPENSSLDIR] [--with-xxx[=vvv]] [--config=FILE] os/compiler[:flags]\n";

# Options:
#
# --config      add the given configuration file, which will be read after
#               any "Configurations*" files that are found in the same
#               directory as this script.
# --prefix      prefix for the OpenSSL installation, which includes the
#               directories bin, lib, include, share/man, share/doc/openssl
#               This becomes the value of INSTALLTOP in Makefile
#               (Default: /usr/local)
# --openssldir  OpenSSL data area, such as openssl.cnf, certificates and keys.
#               If it's a relative directory, it will be added on the directory
#               given with --prefix.
#               This becomes the value of OPENSSLDIR in Makefile and in C.
#               (Default: PREFIX/ssl)
#
# --cross-compile-prefix Add specified prefix to binutils components.
#
# --api         One of 0.9.8, 1.0.0 or 1.1.0.  Do not compile support for
#               interfaces deprecated as of the specified OpenSSL version.
#
# no-hw-xxx     do not compile support for specific crypto hardware.
#               Generic OpenSSL-style methods relating to this support
#               are always compiled but return NULL if the hardware
#               support isn't compiled.
# no-hw         do not compile support for any crypto hardware.
# [no-]threads  [don't] try to create a library that is suitable for
#               multithreaded applications (default is "threads" if we
#               know how to do it)
# [no-]shared   [don't] try to create shared libraries when supported.
# [no-]pic      [don't] try to build position independent code when supported.
#               If disabled, it also disables shared and dynamic-engine.
# no-asm        do not use assembler
# no-egd        do not compile support for the entropy-gathering daemon APIs
# [no-]zlib     [don't] compile support for zlib compression.
# zlib-dynamic  Like "zlib", but the zlib library is expected to be a shared
#               library and will be loaded in run-time by the OpenSSL library.
# sctp          include SCTP support
# enable-weak-ssl-ciphers
#               Enable weak ciphers that are disabled by default.
# 386           generate 80386 code in assembly modules
# no-sse2       disables IA-32 SSE2 code in assembly modules, the above
#               mentioned '386' option implies this one
# no-<cipher>   build without specified algorithm (rsa, idea, rc5, ...)
# -<xxx> +<xxx> All options which are unknown to the 'Configure' script are
# /<xxx>        passed through to the compiler. Unix-style options beginning
#               with a '-' or '+' are recognized, as well as Windows-style
#               options beginning with a '/'. If the option contains arguments
#               separated by spaces, then the URL-style notation %20 can be
#               used for the space character in order to avoid having to quote
#               the option. For example, -opt%20arg gets expanded to -opt arg.
#               In fact, any ASCII character can be encoded as %xx using its
#               hexadecimal encoding.
# -static       while -static is also a pass-through compiler option (and
#               as such is limited to environments where it's actually
#               meaningful), it triggers a number configuration options,
#               namely no-pic, no-shared and no-threads. It is
#               argued that the only reason to produce statically linked
#               binaries (and in context it means executables linked with
#               -static flag, and not just executables linked with static
#               libcrypto.a) is to eliminate dependency on specific run-time,
#               a.k.a. libc version. The mentioned config options are meant
#               to achieve just that. Unfortunately on Linux it's impossible
#               to eliminate the dependency completely for openssl executable
#               because of getaddrinfo and gethostbyname calls, which can
#               invoke dynamically loadable library facility anyway to meet
#               the lookup requests. For this reason on Linux statically
#               linked openssl executable has rather debugging value than
#               production quality.
#
# BN_LLONG      use the type 'long long' in crypto/bn/bn.h
# RC4_CHAR      use 'char' instead of 'int' for RC4_INT in crypto/rc4/rc4.h
# Following are set automatically by this script
#
# MD5_ASM       use some extra md5 assembler,
# SHA1_ASM      use some extra sha1 assembler, must define L_ENDIAN for x86
# RMD160_ASM    use some extra ripemd160 assembler,
# SHA256_ASM    sha256_block is implemented in assembler
# SHA512_ASM    sha512_block is implemented in assembler
# AES_ASM       AES_[en|de]crypt is implemented in assembler

# Minimum warning options... any contributions to OpenSSL should at least
# get past these.  Note that we only use these with C compilers, not with
# C++ compilers.

# DEBUG_UNUSED enables __owur (warn unused result) checks.
# -DPEDANTIC complements -pedantic and is meant to mask code that
# is not strictly standard-compliant and/or implementation-specific,
# e.g. inline assembly, disregards to alignment requirements, such
# that -pedantic would complain about. Incidentally -DPEDANTIC has
# to be used even in sanitized builds, because sanitizer too is
# supposed to and does take notice of non-standard behaviour. Then
# -pedantic with pre-C9x compiler would also complain about 'long
# long' not being supported. As 64-bit algorithms are common now,
# it grew impossible to resolve this without sizeable additional
# code, so we just tell compiler to be pedantic about everything
# but 'long long' type.

my @gcc_devteam_warn = qw(
    -DDEBUG_UNUSED
    -DPEDANTIC -pedantic -Wno-long-long
    -Wall
    -Wextra
    -Wno-unused-parameter
    -Wno-missing-field-initializers
    -Wswitch
    -Wsign-compare
    -Wshadow
    -Wformat
    -Wtype-limits
    -Wundef
    -Werror
    -Wmissing-prototypes
    -Wstrict-prototypes
);

# These are used in addition to $gcc_devteam_warn when the compiler is clang.
# TODO(openssl-team): fix problems and investigate if (at least) the
# following warnings can also be enabled:
#       -Wcast-align
#       -Wunreachable-code -- no, too ugly/compiler-specific
#       -Wlanguage-extension-token -- no, we use asm()
#       -Wunused-macros -- no, too tricky for BN and _XOPEN_SOURCE etc
#       -Wextended-offsetof -- no, needed in CMS ASN1 code
my @clang_devteam_warn = qw(
    -Wno-unknown-warning-option
    -Wswitch-default
    -Wno-parentheses-equality
    -Wno-language-extension-token
    -Wno-extended-offsetof
    -Wconditional-uninitialized
    -Wincompatible-pointer-types-discards-qualifiers
    -Wmissing-variable-declarations
);

my @cl_devteam_warn = qw(
    /WX
);

# This adds backtrace information to the memory leak info.  Is only used
# when crypto-mdebug-backtrace is enabled.
my $memleak_devteam_backtrace = "-rdynamic";

my $strict_warnings = 0;

# As for $BSDthreads. Idea is to maintain "collective" set of flags,
# which would cover all BSD flavors. -pthread applies to them all,
# but is treated differently. OpenBSD expands is as -D_POSIX_THREAD
# -lc_r, which is sufficient. FreeBSD 4.x expands it as -lc_r,
# which has to be accompanied by explicit -D_THREAD_SAFE and
# sometimes -D_REENTRANT. FreeBSD 5.x expands it as -lc_r, which
# seems to be sufficient?
our $BSDthreads="-pthread -D_THREAD_SAFE -D_REENTRANT";

#
# API compatibility name to version number mapping.
#
my $maxapi = "1.1.0";           # API for "no-deprecated" builds
my $apitable = {
    "1.1.0" => "0x10100000L",
    "1.0.0" => "0x10000000L",
    "0.9.8" => "0x00908000L",
};

our %table = ();
our %config = ();
our %withargs = ();
our $now_printing;      # set to current entry's name in print_table_entry
                        # (todo: right thing would be to encapsulate name
                        # into %target [class] and make print_table_entry
                        # a method)

# Forward declarations ###############################################

# read_config(filename)
#
# Reads a configuration file and populates %table with the contents
# (which the configuration file places in %targets).
sub read_config;

# resolve_config(target)
#
# Resolves all the late evaluations, inheritances and so on for the
# chosen target and any target it inherits from.
sub resolve_config;


# Information collection #############################################

# Unified build supports separate build dir
my $srcdir = catdir(absolutedir(dirname($0))); # catdir ensures local syntax
my $blddir = catdir(absolutedir("."));         # catdir ensures local syntax

# File::Spec::Unix doesn't detect case insensitivity, so we make sure to
# check if the source and build directory are really the same, and make
# them so.  This avoids all kinds of confusion later on.
# We must check @File::Spec::ISA rather than using File::Spec->isa() to
# know if File::Spec ended up loading File::Spec::Unix.
$srcdir = $blddir
    if (grep(/::Unix$/, @File::Spec::ISA)
        && samedir($srcdir, $blddir));

my $dofile = abs2rel(catfile($srcdir, "util/dofile.pl"));

my $local_config_envname = 'OPENSSL_LOCAL_CONFIG_DIR';

$config{sourcedir} = abs2rel($srcdir, $blddir);
$config{builddir} = abs2rel($blddir, $blddir);

# Collect reconfiguration information if needed
my @argvcopy=@ARGV;

if (grep /^reconf(igure)?$/, @argvcopy) {
    die "reconfiguring with other arguments present isn't supported"
        if scalar @argvcopy > 1;
    if (-f "./configdata.pm") {
        my $file = "./configdata.pm";
        unless (my $return = do $file) {
            die "couldn't parse $file: $@" if $@;
            die "couldn't do $file: $!"    unless defined $return;
            die "couldn't run $file"       unless $return;
        }

        @argvcopy = defined($configdata::config{perlargv}) ?
            @{$configdata::config{perlargv}} : ();
        die "Incorrect data to reconfigure, please do a normal configuration\n"
            if (grep(/^reconf/,@argvcopy));
        $config{perlenv} = $configdata::config{perlenv} // {};
    } else {
        die "Insufficient data to reconfigure, please do a normal configuration\n";
    }
}

$config{perlargv} = [ @argvcopy ];

# Collect version numbers
$config{version} = "unknown";
$config{version_num} = "unknown";
$config{shlib_version_number} = "unknown";
$config{shlib_version_history} = "unknown";

collect_information(
    collect_from_file(catfile($srcdir,'include/openssl/opensslv.h')),
    qr/OPENSSL.VERSION.TEXT.*OpenSSL (\S+) / => sub { $config{version} = $1; },
    qr/OPENSSL.VERSION.NUMBER.*(0x\S+)/      => sub { $config{version_num}=$1 },
    qr/SHLIB_VERSION_NUMBER *"([^"]+)"/      => sub { $config{shlib_version_number}=$1 },
    qr/SHLIB_VERSION_HISTORY *"([^"]*)"/     => sub { $config{shlib_version_history}=$1 }
    );
if ($config{shlib_version_history} ne "") { $config{shlib_version_history} .= ":"; }

($config{major}, $config{minor})
    = ($config{version} =~ /^([0-9]+)\.([0-9\.]+)/);
($config{shlib_major}, $config{shlib_minor})
    = ($config{shlib_version_number} =~ /^([0-9]+)\.([0-9\.]+)/);
die "erroneous version information in opensslv.h: ",
    "$config{major}, $config{minor}, $config{shlib_major}, $config{shlib_minor}\n"
    if ($config{major} eq "" || $config{minor} eq ""
        || $config{shlib_major} eq "" ||  $config{shlib_minor} eq "");

# Collect target configurations

my $pattern = catfile(dirname($0), "Configurations", "*.conf");
foreach (sort glob($pattern)) {
    &read_config($_);
}

if (defined env($local_config_envname)) {
    if ($^O eq 'VMS') {
        # VMS environment variables are logical names,
        # which can be used as is
        $pattern = $local_config_envname . ':' . '*.conf';
    } else {
        $pattern = catfile(env($local_config_envname), '*.conf');
    }

    foreach (sort glob($pattern)) {
        &read_config($_);
    }
}

# Save away perl command information
$config{perl_cmd} = $^X;
$config{perl_version} = $Config{version};
$config{perl_archname} = $Config{archname};

$config{prefix}="";
$config{openssldir}="";
$config{processor}="";
$config{libdir}="";
my $auto_threads=1;    # enable threads automatically? true by default
my $default_ranlib;

# Top level directories to build
$config{dirs} = [ "crypto", "ssl", "engines", "apps", "test", "util", "tools", "fuzz" ];
# crypto/ subdirectories to build
$config{sdirs} = [
    "objects",
    "md2", "md4", "md5", "sha", "mdc2", "hmac", "ripemd", "whrlpool", "poly1305", "blake2", "siphash", "sm3",
    "des", "aes", "rc2", "rc4", "rc5", "idea", "aria", "bf", "cast", "camellia", "seed", "sm4", "chacha", "modes",
    "bn", "ec", "rsa", "dsa", "dh", "sm2", "dso", "engine",
    "buffer", "bio", "stack", "lhash", "rand", "err",
    "evp", "asn1", "pem", "x509", "x509v3", "conf", "txt_db", "pkcs7", "pkcs12", "comp", "ocsp", "ui",
    "cms", "ts", "srp", "cmac", "ct", "async", "kdf", "store"
    ];
# test/ subdirectories to build
$config{tdirs} = [ "ossl_shim" ];

# Known TLS and DTLS protocols
my @tls = qw(ssl3 tls1 tls1_1 tls1_2 tls1_3);
my @dtls = qw(dtls1 dtls1_2);

# Explicitly known options that are possible to disable.  They can
# be regexps, and will be used like this: /^no-${option}$/
# For developers: keep it sorted alphabetically

my @disablables = (
    "afalgeng",
    "aria",
    "asan",
    "asm",
    "async",
    "autoalginit",
    "autoerrinit",
    "autoload-config",
    "bf",
    "blake2",
    "buildtest-c\\+\\+",
    "camellia",
    "capieng",
    "cast",
    "chacha",
    "cmac",
    "cms",
    "comp",
    "crypto-mdebug",
    "crypto-mdebug-backtrace",
    "ct",
    "deprecated",
    "des",
    "devcryptoeng",
    "dgram",
    "dh",
    "dsa",
    "dso",
    "dtls",
    "dynamic-engine",
    "ec",
    "ec2m",
    "ecdh",
    "ecdsa",
    "ec_nistp_64_gcc_128",
    "egd",
    "engine",
    "err",
    "external-tests",
    "filenames",
    "fuzz-libfuzzer",
    "fuzz-afl",
    "gost",
    "heartbeats",
    "hw(-.+)?",
    "idea",
    "makedepend",
    "md2",
    "md4",
    "mdc2",
    "msan",
    "multiblock",
    "nextprotoneg",
    "pinshared",
    "ocb",
    "ocsp",
    "pic",
    "poly1305",
    "posix-io",
    "psk",
    "rc2",
    "rc4",
    "rc5",
    "rdrand",
    "rfc3779",
    "rmd160",
    "scrypt",
    "sctp",
    "seed",
    "shared",
    "siphash",
    "sm2",
    "sm3",
    "sm4",
    "sock",
    "srp",
    "srtp",
    "sse2",
    "ssl",
    "ssl-trace",
    "static-engine",
    "stdio",
    "tests",
    "threads",
    "tls",
    "ts",
    "ubsan",
    "ui-console",
    "unit-test",
    "whirlpool",
    "weak-ssl-ciphers",
    "zlib",
    "zlib-dynamic",
    );
foreach my $proto ((@tls, @dtls))
        {
        push(@disablables, $proto);
        push(@disablables, "$proto-method") unless $proto eq "tls1_3";
        }

my %deprecated_disablables = (
    "ssl2" => undef,
    "buf-freelists" => undef,
    "ripemd" => "rmd160",
    "ui" => "ui-console",
    );

# All of the following are disabled by default:

our %disabled = ( # "what"         => "comment"
                  "asan"                => "default",
                  "buildtest-c++"       => "default",
                  "crypto-mdebug"       => "default",
                  "crypto-mdebug-backtrace" => "default",
                  "devcryptoeng"        => "default",
                  "ec_nistp_64_gcc_128" => "default",
                  "egd"                 => "default",
                  "external-tests"      => "default",
                  "fuzz-libfuzzer"      => "default",
                  "fuzz-afl"            => "default",
                  "heartbeats"          => "default",
                  "md2"                 => "default",
                  "msan"                => "default",
                  "rc5"                 => "default",
                  "sctp"                => "default",
                  "ssl-trace"           => "default",
                  "ssl3"                => "default",
                  "ssl3-method"         => "default",
                  "ubsan"               => "default",
                  "unit-test"           => "default",
                  "weak-ssl-ciphers"    => "default",
                  "zlib"                => "default",
                  "zlib-dynamic"        => "default",
                );

# Note: => pair form used for aesthetics, not to truly make a hash table
my @disable_cascades = (
    # "what"            => [ "cascade", ... ]
    sub { $config{processor} eq "386" }
                        => [ "sse2" ],
    "ssl"               => [ "ssl3" ],
    "ssl3-method"       => [ "ssl3" ],
    "zlib"              => [ "zlib-dynamic" ],
    "des"               => [ "mdc2" ],
    "ec"                => [ "ecdsa", "ecdh" ],

    "dgram"             => [ "dtls", "sctp" ],
    "sock"              => [ "dgram" ],
    "dtls"              => [ @dtls ],
    sub { 0 == scalar grep { !$disabled{$_} } @dtls }
                        => [ "dtls" ],

    "tls"               => [ @tls ],
    sub { 0 == scalar grep { !$disabled{$_} } @tls }
                        => [ "tls" ],

    "crypto-mdebug"     => [ "crypto-mdebug-backtrace" ],

    # Without position independent code, there can be no shared libraries or DSOs
    "pic"               => [ "shared" ],
    "shared"            => [ "dynamic-engine" ],
    "dso"               => [ "dynamic-engine" ],
    "engine"            => [ "afalgeng", "devcryptoeng" ],

    # no-autoalginit is only useful when building non-shared
    "autoalginit"       => [ "shared", "apps" ],

    "stdio"             => [ "apps", "capieng", "egd" ],
    "apps"              => [ "tests" ],
    "tests"             => [ "external-tests" ],
    "comp"              => [ "zlib" ],
    "ec"                => [ "tls1_3", "sm2" ],
    "sm3"               => [ "sm2" ],
    sub { !$disabled{"unit-test"} } => [ "heartbeats" ],

    sub { !$disabled{"msan"} } => [ "asm" ],
    );

# Avoid protocol support holes.  Also disable all versions below N, if version
# N is disabled while N+1 is enabled.
#
my @list = (reverse @tls);
while ((my $first, my $second) = (shift @list, shift @list)) {
    last unless @list;
    push @disable_cascades, ( sub { !$disabled{$first} && $disabled{$second} }
                              => [ @list ] );
    unshift @list, $second;
}
my @list = (reverse @dtls);
while ((my $first, my $second) = (shift @list, shift @list)) {
    last unless @list;
    push @disable_cascades, ( sub { !$disabled{$first} && $disabled{$second} }
                              => [ @list ] );
    unshift @list, $second;
}

# Explicit "no-..." options will be collected in %disabled along with the defaults.
# To remove something from %disabled, use "enable-foo".
# For symmetry, "disable-foo" is a synonym for "no-foo".

&usage if ($#ARGV < 0);

# For the "make variables" CPPINCLUDES and CPPDEFINES, we support lists with
# platform specific list separators.  Users from those platforms should
# recognise those separators from how you set up the PATH to find executables.
# The default is the Unix like separator, :, but as an exception, we also
# support the space as separator.
my $list_separator_re =
    { VMS           => qr/(?<!\^),/,
      MSWin32       => qr/(?<!\\);/ } -> {$^O} // qr/(?<!\\)[:\s]/;
# All the "make variables" we support
# Some get pre-populated for the sake of backward compatibility
# (we supported those before the change to "make variable" support.
my %user = (
    AR          => env('AR'),
    ARFLAGS     => [],
    AS          => undef,
    ASFLAGS     => [],
    CC          => env('CC'),
    CFLAGS      => [ env('CFLAGS') || () ],
    CXX         => env('CXX'),
    CXXFLAGS    => [ env('CXXFLAGS') || () ],
    CPP         => undef,
    CPPFLAGS    => [ env('CPPFLAGS') || () ],  # -D, -I, -Wp,
    CPPDEFINES  => [],  # Alternative for -D
    CPPINCLUDES => [],  # Alternative for -I
    CROSS_COMPILE => env('CROSS_COMPILE'),
    HASHBANGPERL=> env('HASHBANGPERL') || env('PERL'),
    LD          => undef,
    LDFLAGS     => [ env('LDFLAGS') || () ],  # -L, -Wl,
    LDLIBS      => [ env('LDLIBS') || () ],  # -l
    MT          => undef,
    MTFLAGS     => [],
    PERL        => env('PERL') || ($^O ne "VMS" ? $^X : "perl"),
    RANLIB      => env('RANLIB'),
    RC          => env('RC') || env('WINDRES'),
    RCFLAGS     => [ env('RCFLAGS') || () ],
    RM          => undef,
   );
# Info about what "make variables" may be prefixed with the cross compiler
# prefix.  This should NEVER mention any such variable with a list for value.
my @user_crossable = qw ( AR AS CC CXX CPP LD MT RANLIB RC );
# The same but for flags given as Configure options.  These are *additional*
# input, as opposed to the VAR=string option that override the corresponding
# config target attributes
my %useradd = (
    CPPDEFINES  => [],
    CPPINCLUDES => [],
    CPPFLAGS    => [],
    CFLAGS      => [],
    CXXFLAGS    => [],
    LDFLAGS     => [],
    LDLIBS      => [],
    RCFLAGS     => [],
   );

my %user_synonyms = (
    HASHBANGPERL=> 'PERL',
    RC          => 'WINDRES',
   );

# Some target attributes have been renamed, this is the translation table
my %target_attr_translate =(
    ar          => 'AR',
    as          => 'AS',
    cc          => 'CC',
    cxx         => 'CXX',
    cpp         => 'CPP',
    hashbangperl => 'HASHBANGPERL',
    ld          => 'LD',
    mt          => 'MT',
    ranlib      => 'RANLIB',
    rc          => 'RC',
    rm          => 'RM',
   );

# Initialisers coming from 'config' scripts
$config{defines} = [ split(/$list_separator_re/, env('__CNF_CPPDEFINES')) ];
$config{includes} = [ split(/$list_separator_re/, env('__CNF_CPPINCLUDES')) ];
$config{cppflags} = [ env('__CNF_CPPFLAGS') || () ];
$config{cflags} = [ env('__CNF_CFLAGS') || () ];
$config{cxxflags} = [ env('__CNF_CXXFLAGS') || () ];
$config{lflags} = [ env('__CNF_LDFLAGS') || () ];
$config{ex_libs} = [ env('__CNF_LDLIBS') || () ];

$config{openssl_api_defines}=[];
$config{openssl_algorithm_defines}=[];
$config{openssl_thread_defines}=[];
$config{openssl_sys_defines}=[];
$config{openssl_other_defines}=[];
$config{options}="";
$config{build_type} = "release";
my $target="";

my %cmdvars = ();               # Stores FOO='blah' type arguments
my %unsupported_options = ();
my %deprecated_options = ();
# If you change this, update apps/version.c
my @known_seed_sources = qw(getrandom devrandom os egd none rdcpu librandom);
my @seed_sources = ();
while (@argvcopy)
        {
        $_ = shift @argvcopy;

        # Support env variable assignments among the options
        if (m|^(\w+)=(.+)?$|)
                {
                $cmdvars{$1} = $2;
                # Every time a variable is given as a configuration argument,
                # it acts as a reset if the variable.
                if (exists $user{$1})
                        {
                        $user{$1} = ref $user{$1} eq "ARRAY" ? [] : undef;
                        }
                #if (exists $useradd{$1})
                #       {
                #       $useradd{$1} = [];
                #       }
                next;
                }

        # VMS is a case insensitive environment, and depending on settings
        # out of our control, we may receive options uppercased.  Let's
        # downcase at least the part before any equal sign.
        if ($^O eq "VMS")
                {
                s/^([^=]*)/lc($1)/e;
                }

        # some people just can't read the instructions, clang people have to...
        s/^-no-(?!integrated-as)/no-/;

        # rewrite some options in "enable-..." form
        s /^-?-?shared$/enable-shared/;
        s /^sctp$/enable-sctp/;
        s /^threads$/enable-threads/;
        s /^zlib$/enable-zlib/;
        s /^zlib-dynamic$/enable-zlib-dynamic/;

        if (/^(no|disable|enable)-(.+)$/)
                {
                my $word = $2;
                if (!exists $deprecated_disablables{$word}
                        && !grep { $word =~ /^${_}$/ } @disablables)
                        {
                        $unsupported_options{$_} = 1;
                        next;
                        }
                }
        if (/^no-(.+)$/ || /^disable-(.+)$/)
                {
                foreach my $proto ((@tls, @dtls))
                        {
                        if ($1 eq "$proto-method")
                                {
                                $disabled{"$proto"} = "option($proto-method)";
                                last;
                                }
                        }
                if ($1 eq "dtls")
                        {
                        foreach my $proto (@dtls)
                                {
                                $disabled{$proto} = "option(dtls)";
                                }
                        $disabled{"dtls"} = "option(dtls)";
                        }
                elsif ($1 eq "ssl")
                        {
                        # Last one of its kind
                        $disabled{"ssl3"} = "option(ssl)";
                        }
                elsif ($1 eq "tls")
                        {
                        # XXX: Tests will fail if all SSL/TLS
                        # protocols are disabled.
                        foreach my $proto (@tls)
                                {
                                $disabled{$proto} = "option(tls)";
                                }
                        }
                elsif ($1 eq "static-engine")
                        {
                        delete $disabled{"dynamic-engine"};
                        }
                elsif ($1 eq "dynamic-engine")
                        {
                        $disabled{"dynamic-engine"} = "option";
                        }
                elsif (exists $deprecated_disablables{$1})
                        {
                        if ($deprecated_disablables{$1} ne "")
                                {
                                $deprecated_options{$_} = 1;
                                if (defined $deprecated_disablables{$1})
                                        {
                                        $disabled{$deprecated_disablables{$1}} = "option";
                                        }
                                }
                        }
                else
                        {
                        $disabled{$1} = "option";
                        }
                # No longer an automatic choice
                $auto_threads = 0 if ($1 eq "threads");
                }
        elsif (/^enable-(.+)$/)
                {
                if ($1 eq "static-engine")
                        {
                        $disabled{"dynamic-engine"} = "option";
                        }
                elsif ($1 eq "dynamic-engine")
                        {
                        delete $disabled{"dynamic-engine"};
                        }
                elsif ($1 eq "zlib-dynamic")
                        {
                        delete $disabled{"zlib"};
                        }
                my $algo = $1;
                delete $disabled{$algo};

                # No longer an automatic choice
                $auto_threads = 0 if ($1 eq "threads");
                }
        elsif (/^--strict-warnings$/)
                {
                # Pretend that our strict flags is a C flag, and replace it
                # with the proper flags later on
                push @{$useradd{CFLAGS}}, '--ossl-strict-warnings';
                $strict_warnings=1;
                }
        elsif (/^--debug$/)
                {
                $config{build_type} = "debug";
                }
        elsif (/^--release$/)
                {
                $config{build_type} = "release";
                }
        elsif (/^386$/)
                { $config{processor}=386; }
        elsif (/^fips$/)
                {
                die "FIPS mode not supported\n";
                }
        elsif (/^rsaref$/)
                {
                # No RSAref support any more since it's not needed.
                # The check for the option is there so scripts aren't
                # broken
                }
        elsif (/^nofipscanistercheck$/)
                {
                die "FIPS mode not supported\n";
                }
        elsif (m|^[-+/]|)
                {
                if (/^--prefix=(.*)$/)
                        {
                        $config{prefix}=$1;
                        die "Directory given with --prefix MUST be absolute\n"
                                unless file_name_is_absolute($config{prefix});
                        }
                elsif (/^--api=(.*)$/)
                        {
                        $config{api}=$1;
                        }
                elsif (/^--libdir=(.*)$/)
                        {
                        $config{libdir}=$1;
                        }
                elsif (/^--openssldir=(.*)$/)
                        {
                        $config{openssldir}=$1;
                        }
                elsif (/^--with-zlib-lib=(.*)$/)
                        {
                        $withargs{zlib_lib}=$1;
                        }
                elsif (/^--with-zlib-include=(.*)$/)
                        {
                        $withargs{zlib_include}=$1;
                        }
                elsif (/^--with-fuzzer-lib=(.*)$/)
                        {
                        $withargs{fuzzer_lib}=$1;
                        }
                elsif (/^--with-fuzzer-include=(.*)$/)
                        {
                        $withargs{fuzzer_include}=$1;
                        }
                elsif (/^--with-rand-seed=(.*)$/)
                        {
                        foreach my $x (split(m|,|, $1))
                            {
                            die "Unknown --with-rand-seed choice $x\n"
                                if ! grep { $x eq $_ } @known_seed_sources;
                            push @seed_sources, $x;
                            }
                        }
                elsif (/^--cross-compile-prefix=(.*)$/)
                        {
                        $user{CROSS_COMPILE}=$1;
                        }
                elsif (/^--config=(.*)$/)
                        {
                        read_config $1;
                        }
                elsif (/^-l(.*)$/)
                        {
                        push @{$useradd{LDLIBS}}, $_;
                        }
                elsif (/^-framework$/)
                        {
                        push @{$useradd{LDLIBS}}, $_, shift(@argvcopy);
                        }
                elsif (/^-L(.*)$/ or /^-Wl,/)
                        {
                        push @{$useradd{LDFLAGS}}, $_;
                        }
                elsif (/^-rpath$/ or /^-R$/)
                        # -rpath is the OSF1 rpath flag
                        # -R is the old Solaris rpath flag
                        {
                        my $rpath = shift(@argvcopy) || "";
                        $rpath .= " " if $rpath ne "";
                        push @{$useradd{LDFLAGS}}, $_, $rpath;
                        }
                elsif (/^-static$/)
                        {
                        push @{$useradd{LDFLAGS}}, $_;
                        }
                elsif (m|^[-/]D(.*)$|)
                        {
                        push @{$useradd{CPPDEFINES}}, $1;
                        }
                elsif (m|^[-/]I(.*)$|)
                        {
                        push @{$useradd{CPPINCLUDES}}, $1;
                        }
                elsif (/^-Wp,$/)
                        {
                        push @{$useradd{CPPFLAGS}}, $1;
                        }
                else    # common if (/^[-+]/), just pass down...
                        {
                        # Treat %xx as an ASCII code (e.g. replace %20 by a space character).
                        # This provides a simple way to pass options with arguments separated
                        # by spaces without quoting (e.g. -opt%20arg translates to -opt arg).
                        $_ =~ s/%([0-9a-f]{1,2})/chr(hex($1))/gei;
                        push @{$useradd{CFLAGS}}, $_;
                        push @{$useradd{CXXFLAGS}}, $_;
                        }
                }
        elsif (m|^/|)
                {
                # Treat %xx as an ASCII code (e.g. replace %20 by a space character).
                # This provides a simple way to pass options with arguments separated
                # by spaces without quoting (e.g. /opt%20arg translates to /opt arg).
                $_ =~ s/%([0-9a-f]{1,2})/chr(hex($1))/gei;
                push @{$useradd{CFLAGS}}, $_;
                push @{$useradd{CXXFLAGS}}, $_;
                }
        else
                {
                die "target already defined - $target (offending arg: $_)\n" if ($target ne "");
                $target=$_;
                }
        unless ($_ eq $target || /^no-/ || /^disable-/)
                {
                # "no-..." follows later after implied deactivations
                # have been derived.  (Don't take this too seriously,
                # we really only write OPTIONS to the Makefile out of
                # nostalgia.)

                if ($config{options} eq "")
                        { $config{options} = $_; }
                else
                        { $config{options} .= " ".$_; }
                }
        }

if (defined($config{api}) && !exists $apitable->{$config{api}}) {
        die "***** Unsupported api compatibility level: $config{api}\n",
}

if (keys %deprecated_options)
        {
        warn "***** Deprecated options: ",
                join(", ", keys %deprecated_options), "\n";
        }
if (keys %unsupported_options)
        {
        die "***** Unsupported options: ",
                join(", ", keys %unsupported_options), "\n";
        }

# If any %useradd entry has been set, we must check that the "make
# variables" haven't been set.  We start by checking of any %useradd entry
# is set.
if (grep { scalar @$_ > 0 } values %useradd) {
    # Hash of env / make variables names.  The possible values are:
    # 1 - "make vars"
    # 2 - %useradd entry set
    # 3 - both set
    my %detected_vars =
        map { my $v = 0;
              $v += 1 if $cmdvars{$_};
              $v += 2 if @{$useradd{$_}};
              $_ => $v }
        keys %useradd;

    # If any of the corresponding "make variables" is set, we error
    if (grep { $_ & 1 } values %detected_vars) {
        my $names = join(', ', grep { $detected_vars{$_} > 0 }
                               sort keys %detected_vars);
        die <<"_____";
***** Mixing make variables and additional compiler/linker flags as
***** configure command line option is not permitted.
***** Affected make variables: $names
_____
    }
}

# Check through all supported command line variables to see if any of them
# were set, and canonicalise the values we got.  If no compiler or linker
# flag or anything else that affects %useradd was set, we also check the
# environment for values.
my $anyuseradd =
    grep { defined $_ && (ref $_ ne 'ARRAY' || @$_) } values %useradd;
foreach (keys %user) {
    my $value = $cmdvars{$_};
    $value //= env($_) unless $anyuseradd;
    $value //=
        defined $user_synonyms{$_} ? $cmdvars{$user_synonyms{$_}} : undef;
    $value //= defined $user_synonyms{$_} ? env($user_synonyms{$_}) : undef
        unless $anyuseradd;

    if (defined $value) {
        if (ref $user{$_} eq 'ARRAY') {
            if ($_ eq 'CPPDEFINES' || $_ eq 'CPPINCLUDES') {
                $user{$_} = [ split /$list_separator_re/, $value ];
            } else {
                $user{$_} = [ $value ];
            }
        } elsif (!defined $user{$_}) {
            $user{$_} = $value;
        }
    }
}

if (grep { /-rpath\b/ } ($user{LDFLAGS} ? @{$user{LDFLAGS}} : ())
    && !$disabled{shared}
    && !($disabled{asan} && $disabled{msan} && $disabled{ubsan})) {
    die "***** Cannot simultaneously use -rpath, shared libraries, and\n",
        "***** any of asan, msan or ubsan\n";
}

sub disable {
    my $disable_type = shift;

    for (@_) {
        $disabled{$_} = $disable_type;
    }

    my @tocheckfor = (@_ ? @_ : keys %disabled);
    while (@tocheckfor) {
        my %new_tocheckfor = ();
        my @cascade_copy = (@disable_cascades);
        while (@cascade_copy) {
            my ($test, $descendents) =
                (shift @cascade_copy, shift @cascade_copy);
            if (ref($test) eq "CODE" ? $test->() : defined($disabled{$test})) {
                foreach (grep { !defined($disabled{$_}) } @$descendents) {
                    $new_tocheckfor{$_} = 1; $disabled{$_} = "cascade";
                }
            }
        }
        @tocheckfor = (keys %new_tocheckfor);
    }
}
disable();                     # First cascade run

our $die = sub { die @_; };
if ($target eq "TABLE") {
    local $die = sub { warn @_; };
    foreach (sort keys %table) {
        print_table_entry($_, "TABLE");
    }
    exit 0;
}

if ($target eq "LIST") {
    foreach (sort keys %table) {
        print $_,"\n" unless $table{$_}->{template};
    }
    exit 0;
}

if ($target eq "HASH") {
    local $die = sub { warn @_; };
    print "%table = (\n";
    foreach (sort keys %table) {
        print_table_entry($_, "HASH");
    }
    exit 0;
}

print "Configuring OpenSSL version $config{version} ($config{version_num}) ";
print "for $target\n";

if (scalar(@seed_sources) == 0) {
    print "Using os-specific seed configuration\n";
    push @seed_sources, 'os';
}
if (scalar(grep { $_ eq 'egd' } @seed_sources) > 0) {
    delete $disabled{'egd'};
}
if (scalar(grep { $_ eq 'none' } @seed_sources) > 0) {
    die "Cannot seed with none and anything else" if scalar(@seed_sources) > 1;
    warn <<_____ if scalar(@seed_sources) == 1;

============================== WARNING ===============================
You have selected the --with-rand-seed=none option, which effectively
disables automatic reseeding of the OpenSSL random generator.
All operations depending on the random generator such as creating keys
will not work unless the random generator is seeded manually by the
application.

Please read the 'Note on random number generation' section in the
INSTALL instructions and the RAND_DRBG(7) manual page for more details.
============================== WARNING ===============================

_____
}
push @{$config{openssl_other_defines}},
     map { (my $x = $_) =~ tr|[\-a-z]|[_A-Z]|; "OPENSSL_RAND_SEED_$x" }
        @seed_sources;

# Backward compatibility?
if ($target =~ m/^CygWin32(-.*)$/) {
    $target = "Cygwin".$1;
}

# Support for legacy targets having a name starting with 'debug-'
my ($d, $t) = $target =~ m/^(debug-)?(.*)$/;
if ($d) {
    $config{build_type} = "debug";

    # If we do not find debug-foo in the table, the target is set to foo.
    if (!$table{$target}) {
        $target = $t;
    }
}

&usage if !$table{$target} || $table{$target}->{template};

$config{target} = $target;
my %target = resolve_config($target);

foreach (keys %target_attr_translate) {
    $target{$target_attr_translate{$_}} = $target{$_}
        if $target{$_};
    delete $target{$_};
}

%target = ( %{$table{DEFAULTS}}, %target );

my %conf_files = map { $_ => 1 } (@{$target{_conf_fname_int}});
$config{conf_files} = [ sort keys %conf_files ];

# Using sub disable within these loops may prove fragile, so we run
# a cascade afterwards
foreach my $feature (@{$target{disable}}) {
    if (exists $deprecated_disablables{$feature}) {
        warn "***** config $target disables deprecated feature $feature\n";
    } elsif (!grep { $feature eq $_ } @disablables) {
        die "***** config $target disables unknown feature $feature\n";
    }
    $disabled{$feature} = 'config';
}
foreach my $feature (@{$target{enable}}) {
    if ("default" eq ($disabled{$feature} // "")) {
        if (exists $deprecated_disablables{$feature}) {
            warn "***** config $target enables deprecated feature $feature\n";
        } elsif (!grep { $feature eq $_ } @disablables) {
            die "***** config $target enables unknown feature $feature\n";
        }
        delete $disabled{$feature};
    }
}
disable();                      # Run a cascade now

$target{CXXFLAGS}//=$target{CFLAGS} if $target{CXX};
$target{cxxflags}//=$target{cflags} if $target{CXX};
$target{exe_extension}="";
$target{exe_extension}=".exe" if ($config{target} eq "DJGPP"
                                  || $config{target} =~ /^(?:Cygwin|mingw)/);
$target{exe_extension}=".pm"  if ($config{target} =~ /vos/);

($target{shared_extension_simple}=$target{shared_extension})
    =~ s|\.\$\(SHLIB_VERSION_NUMBER\)||
    unless defined($target{shared_extension_simple});
$target{dso_extension}//=$target{shared_extension_simple};
($target{shared_import_extension}=$target{shared_extension_simple}.".a")
    if ($config{target} =~ /^(?:Cygwin|mingw)/);

# Fill %config with values from %user, and in case those are undefined or
# empty, use values from %target (acting as a default).
foreach (keys %user) {
    my $ref_type = ref $user{$_};

    # Temporary function.  Takes an intended ref type (empty string or "ARRAY")
    # and a value that's to be coerced into that type.
    my $mkvalue = sub {
        my $type = shift;
        my $value = shift;
        my $undef_p = shift;

        die "Too many arguments for \$mkvalue" if @_;

        while (ref $value eq 'CODE') {
            $value = $value->();
        }

        if ($type eq 'ARRAY') {
            return undef unless defined $value;
            return undef if ref $value ne 'ARRAY' && !$value;
            return undef if ref $value eq 'ARRAY' && !@$value;
            return [ $value ] unless ref $value eq 'ARRAY';
        }
        return undef unless $value;
        return $value;
    };

    $config{$_} =
        $mkvalue->($ref_type, $user{$_})
        || $mkvalue->($ref_type, $target{$_});
    delete $config{$_} unless defined $config{$_};
}

# Finish up %config by appending things the user gave us on the command line
# apart from "make variables"
foreach (keys %useradd) {
    # The must all be lists, so we assert that here
    die "internal error: \$useradd{$_} isn't an ARRAY\n"
        unless ref $useradd{$_} eq 'ARRAY';

    if (defined $config{$_}) {
        push @{$config{$_}}, @{$useradd{$_}};
    } else {
        $config{$_} = [ @{$useradd{$_}} ];
    }
}
# At this point, we can forget everything about %user and %useradd,
# because it's now all been merged into the corresponding $config entry

if (grep { $_ eq '-static' } @{$config{LDFLAGS}}) {
    disable('static', 'pic', 'threads');
}

# Allow overriding the build file name
$config{build_file} = env('BUILDFILE') || $target{build_file} || "Makefile";

# Make sure build_scheme is consistent.
$target{build_scheme} = [ $target{build_scheme} ]
    if ref($target{build_scheme}) ne "ARRAY";

my ($builder, $builder_platform, @builder_opts) =
    @{$target{build_scheme}};

foreach my $checker (($builder_platform."-".$target{build_file}."-checker.pm",
                      $builder_platform."-checker.pm")) {
    my $checker_path = catfile($srcdir, "Configurations", $checker);
    if (-f $checker_path) {
        my $fn = $ENV{CONFIGURE_CHECKER_WARN}
            ? sub { warn $@; } : sub { die $@; };
        if (! do $checker_path) {
            if ($@) {
                $fn->($@);
            } elsif ($!) {
                $fn->($!);
            } else {
                $fn->("The detected tools didn't match the platform\n");
            }
        }
        last;
    }
}

push @{$config{defines}}, "NDEBUG"    if $config{build_type} eq "release";

if ($target =~ /^mingw/ && `$config{CC} --target-help 2>&1` =~ m/-mno-cygwin/m)
        {
        push @{$config{cflags}}, "-mno-cygwin";
        push @{$config{cxxflags}}, "-mno-cygwin" if $config{CXX};
        push @{$config{shared_ldflag}}, "-mno-cygwin";
        }

if ($target =~ /linux.*-mips/ && !$disabled{asm}
        && !grep { $_ !~ /-m(ips|arch=)/ } (@{$config{CFLAGS}})) {
        # minimally required architecture flags for assembly modules
        my $value;
        $value = '-mips2' if ($target =~ /mips32/);
        $value = '-mips3' if ($target =~ /mips64/);
        unshift @{$config{cflags}}, $value;
        unshift @{$config{cxxflags}}, $value if $config{CXX};
}

# If threads aren't disabled, check how possible they are
unless ($disabled{threads}) {
    if ($auto_threads) {
        # Enabled by default, disable it forcibly if unavailable
        if ($target{thread_scheme} eq "(unknown)") {
            disable("unavailable", 'threads');
        }
    } else {
        # The user chose to enable threads explicitly, let's see
        # if there's a chance that's possible
        if ($target{thread_scheme} eq "(unknown)") {
            # If the user asked for "threads" and we don't have internal
            # knowledge how to do it, [s]he is expected to provide any
            # system-dependent compiler options that are necessary.  We
            # can't truly check that the given options are correct, but
            # we expect the user to know what [s]He is doing.
            if (!@{$config{CFLAGS}} && !@{$config{CPPDEFINES}}) {
                die "You asked for multi-threading support, but didn't\n"
                    ,"provide any system-specific compiler options\n";
            }
        }
    }
}

# If threads still aren't disabled, add a C macro to ensure the source
# code knows about it.  Any other flag is taken care of by the configs.
unless($disabled{threads}) {
    push @{$config{openssl_thread_defines}}, "OPENSSL_THREADS";
}

# With "deprecated" disable all deprecated features.
if (defined($disabled{"deprecated"})) {
        $config{api} = $maxapi;
}

my $no_shared_warn=0;
if ($target{shared_target} eq "")
        {
        $no_shared_warn = 1
            if (!$disabled{shared} || !$disabled{"dynamic-engine"});
        disable('no-shared-target', 'pic');
        }

if ($disabled{"dynamic-engine"}) {
        $config{dynamic_engines} = 0;
} else {
        $config{dynamic_engines} = 1;
}

unless ($disabled{asan}) {
    push @{$config{cflags}}, "-fsanitize=address";
}

unless ($disabled{ubsan}) {
    # -DPEDANTIC or -fnosanitize=alignment may also be required on some
    # platforms.
    push @{$config{cflags}}, "-fsanitize=undefined", "-fno-sanitize-recover=all";
}

unless ($disabled{msan}) {
  push @{$config{cflags}}, "-fsanitize=memory";
}

unless ($disabled{"fuzz-libfuzzer"} && $disabled{"fuzz-afl"}
        && $disabled{asan} && $disabled{ubsan} && $disabled{msan}) {
    push @{$config{cflags}}, "-fno-omit-frame-pointer", "-g";
    push @{$config{cxxflags}}, "-fno-omit-frame-pointer", "-g" if $config{CXX};
}
#
# Platform fix-ups
#

# This saves the build files from having to check
if ($disabled{pic})
        {
        foreach (qw(shared_cflag shared_cxxflag shared_cppflag
                    shared_defines shared_includes shared_ldflag
                    module_cflags module_cxxflags module_cppflags
                    module_defines module_includes module_lflags))
                {
                delete $config{$_};
                $target{$_} = "";
                }
        }
else
        {
        push @{$config{lib_defines}}, "OPENSSL_PIC";
        }

if ($target{sys_id} ne "")
        {
        push @{$config{openssl_sys_defines}}, "OPENSSL_SYS_$target{sys_id}";
        }

unless ($disabled{asm}) {
    $target{cpuid_asm_src}=$table{DEFAULTS}->{cpuid_asm_src} if ($config{processor} eq "386");
    push @{$config{lib_defines}}, "OPENSSL_CPUID_OBJ" if ($target{cpuid_asm_src} ne "mem_clr.c");

    $target{bn_asm_src} =~ s/\w+-gf2m.c// if (defined($disabled{ec2m}));

    # bn-586 is the only one implementing bn_*_part_words
    push @{$config{lib_defines}}, "OPENSSL_BN_ASM_PART_WORDS" if ($target{bn_asm_src} =~ /bn-586/);
    push @{$config{lib_defines}}, "OPENSSL_IA32_SSE2" if (!$disabled{sse2} && $target{bn_asm_src} =~ /86/);

    push @{$config{lib_defines}}, "OPENSSL_BN_ASM_MONT" if ($target{bn_asm_src} =~ /-mont/);
    push @{$config{lib_defines}}, "OPENSSL_BN_ASM_MONT5" if ($target{bn_asm_src} =~ /-mont5/);
    push @{$config{lib_defines}}, "OPENSSL_BN_ASM_GF2m" if ($target{bn_asm_src} =~ /-gf2m/);
    push @{$config{lib_defines}}, "BN_DIV3W" if ($target{bn_asm_src} =~ /-div3w/);

    if ($target{sha1_asm_src}) {
        push @{$config{lib_defines}}, "SHA1_ASM"   if ($target{sha1_asm_src} =~ /sx86/ || $target{sha1_asm_src} =~ /sha1/);
        push @{$config{lib_defines}}, "SHA256_ASM" if ($target{sha1_asm_src} =~ /sha256/);
        push @{$config{lib_defines}}, "SHA512_ASM" if ($target{sha1_asm_src} =~ /sha512/);
    }
    if ($target{keccak1600_asm_src} ne $table{DEFAULTS}->{keccak1600_asm_src}) {
        push @{$config{lib_defines}}, "KECCAK1600_ASM";
    }
    if ($target{rc4_asm_src} ne $table{DEFAULTS}->{rc4_asm_src}) {
        push @{$config{lib_defines}}, "RC4_ASM";
    }
    if ($target{md5_asm_src}) {
        push @{$config{lib_defines}}, "MD5_ASM";
    }
    $target{cast_asm_src}=$table{DEFAULTS}->{cast_asm_src} unless $disabled{pic}; # CAST assembler is not PIC
    if ($target{rmd160_asm_src}) {
        push @{$config{lib_defines}}, "RMD160_ASM";
    }
    if ($target{aes_asm_src}) {
        push @{$config{lib_defines}}, "AES_ASM" if ($target{aes_asm_src} =~ m/\baes-/);;
        push @{$config{lib_defines}}, "AESNI_ASM" if ($target{aes_asm_src} =~ m/\baesni-/);;
        # aes-ctr.fake is not a real file, only indication that assembler
        # module implements AES_ctr32_encrypt...
        push @{$config{lib_defines}}, "AES_CTR_ASM" if ($target{aes_asm_src} =~ s/\s*aes-ctr\.fake//);
        # aes-xts.fake indicates presence of AES_xts_[en|de]crypt...
        push @{$config{lib_defines}}, "AES_XTS_ASM" if ($target{aes_asm_src} =~ s/\s*aes-xts\.fake//);
        $target{aes_asm_src} =~ s/\s*(vpaes|aesni)-x86\.s//g if ($disabled{sse2});
        push @{$config{lib_defines}}, "VPAES_ASM" if ($target{aes_asm_src} =~ m/vpaes/);
        push @{$config{lib_defines}}, "BSAES_ASM" if ($target{aes_asm_src} =~ m/bsaes/);
    }
    if ($target{wp_asm_src} =~ /mmx/) {
        if ($config{processor} eq "386") {
            $target{wp_asm_src}=$table{DEFAULTS}->{wp_asm_src};
        } elsif (!$disabled{"whirlpool"}) {
            push @{$config{lib_defines}}, "WHIRLPOOL_ASM";
        }
    }
    if ($target{modes_asm_src} =~ /ghash-/) {
        push @{$config{lib_defines}}, "GHASH_ASM";
    }
    if ($target{ec_asm_src} =~ /ecp_nistz256/) {
        push @{$config{lib_defines}}, "ECP_NISTZ256_ASM";
    }
    if ($target{ec_asm_src} =~ /x25519/) {
        push @{$config{lib_defines}}, "X25519_ASM";
    }
    if ($target{padlock_asm_src} ne $table{DEFAULTS}->{padlock_asm_src}) {
        push @{$config{dso_defines}}, "PADLOCK_ASM";
    }
    if ($target{poly1305_asm_src} ne "") {
        push @{$config{lib_defines}}, "POLY1305_ASM";
    }
}

my %predefined_C = compiler_predefined($config{CROSS_COMPILE}.$config{CC});
my %predefined_CXX = $config{CXX}
    ? compiler_predefined($config{CROSS_COMPILE}.$config{CXX})
    : ();

# Check for makedepend capabilities.
if (!$disabled{makedepend}) {
    if ($config{target} =~ /^(VC|vms)-/) {
        # For VC- and vms- targets, there's nothing more to do here.  The
        # functionality is hard coded in the corresponding build files for
        # cl (Windows) and CC/DECC (VMS).
    } elsif (($predefined_C{__GNUC__} // -1) >= 3
             && !($predefined_C{__APPLE_CC__} && !$predefined_C{__clang__})) {
        # We know that GNU C version 3 and up as well as all clang
        # versions support dependency generation, but Xcode did not
        # handle $cc -M before clang support (but claims __GNUC__ = 3)
        $config{makedepprog} = "\$(CROSS_COMPILE)$config{CC}";
    } else {
        # In all other cases, we look for 'makedepend', and disable the
        # capability if not found.
        $config{makedepprog} = which('makedepend');
        disable('unavailable', 'makedepend') unless $config{makedepprog};
    }
}

if (!$disabled{asm} && !$predefined_C{__MACH__} && $^O ne 'VMS') {
    # probe for -Wa,--noexecstack option...
    if ($predefined_C{__clang__}) {
        # clang has builtin assembler, which doesn't recognize --help,
        # but it apparently recognizes the option in question on all
        # supported platforms even when it's meaningless. In other words
        # probe would fail, but probed option always accepted...
        push @{$config{cflags}}, "-Wa,--noexecstack", "-Qunused-arguments";
    } else {
        my $cc = $config{CROSS_COMPILE}.$config{CC};
        open(PIPE, "$cc -Wa,--help -c -o null.$$.o -x assembler /dev/null 2>&1 |");
        while(<PIPE>) {
            if (m/--noexecstack/) {
                push @{$config{cflags}}, "-Wa,--noexecstack";
                last;
            }
        }
        close(PIPE);
        unlink("null.$$.o");
    }
}

# Deal with bn_ops ###################################################

$config{bn_ll}                  =0;
$config{export_var_as_fn}       =0;
my $def_int="unsigned int";
$config{rc4_int}                =$def_int;
($config{b64l},$config{b64},$config{b32})=(0,0,1);

my $count = 0;
foreach (sort split(/\s+/,$target{bn_ops})) {
    $count++ if /SIXTY_FOUR_BIT|SIXTY_FOUR_BIT_LONG|THIRTY_TWO_BIT/;
    $config{export_var_as_fn}=1                 if $_ eq 'EXPORT_VAR_AS_FN';
    $config{bn_ll}=1                            if $_ eq 'BN_LLONG';
    $config{rc4_int}="unsigned char"            if $_ eq 'RC4_CHAR';
    ($config{b64l},$config{b64},$config{b32})
        =(0,1,0)                                if $_ eq 'SIXTY_FOUR_BIT';
    ($config{b64l},$config{b64},$config{b32})
        =(1,0,0)                                if $_ eq 'SIXTY_FOUR_BIT_LONG';
    ($config{b64l},$config{b64},$config{b32})
        =(0,0,1)                                if $_ eq 'THIRTY_TWO_BIT';
}
die "Exactly one of SIXTY_FOUR_BIT|SIXTY_FOUR_BIT_LONG|THIRTY_TWO_BIT can be set in bn_ops\n"
    if $count > 1;


# Hack cflags for better warnings (dev option) #######################

# "Stringify" the C and C++ flags string.  This permits it to be made part of
# a string and works as well on command lines.
$config{cflags} = [ map { (my $x = $_) =~ s/([\\\"])/\\$1/g; $x }
                        @{$config{cflags}} ];
$config{cxxflags} = [ map { (my $x = $_) =~ s/([\\\"])/\\$1/g; $x }
                          @{$config{cxxflags}} ] if $config{CXX};

if (defined($config{api})) {
    $config{openssl_api_defines} = [ "OPENSSL_MIN_API=".$apitable->{$config{api}} ];
    my $apiflag = sprintf("OPENSSL_API_COMPAT=%s", $apitable->{$config{api}});
    push @{$config{defines}}, $apiflag;
}

my @strict_warnings_collection=();
if ($strict_warnings)
        {
        my $wopt;
        my $gccver = $predefined_C{__GNUC__} // -1;

        if ($gccver >= 4)
                {
                push @strict_warnings_collection, @gcc_devteam_warn;
                push @strict_warnings_collection, @clang_devteam_warn
                    if (defined($predefined_C{__clang__}));
                }
        elsif ($config{target} =~ /^VC-/)
                {
                push @strict_warnings_collection, @cl_devteam_warn;
                }
        else
                {
                warn "WARNING --strict-warnings requires gcc[>=4] or gcc-alike, or MSVC"
                }
        }

$config{CFLAGS} = [ map { $_ eq '--ossl-strict-warnings'
                              ? @strict_warnings_collection
                              : ( $_ ) }
                    @{$config{CFLAGS}} ];

unless ($disabled{"crypto-mdebug-backtrace"})
        {
        foreach my $wopt (split /\s+/, $memleak_devteam_backtrace)
                {
                push @{$config{cflags}}, $wopt
                        unless grep { $_ eq $wopt } @{$config{cflags}};
                }
        if ($target =~ /^BSD-/)
                {
                push @{$config{ex_libs}}, "-lexecinfo";
                }
        }

unless ($disabled{afalgeng}) {
    $config{afalgeng}="";
    if (grep { $_ eq 'afalgeng' } @{$target{enable}}) {
        my $minver = 4*10000 + 1*100 + 0;
        if ($config{CROSS_COMPILE} eq "") {
            my $verstr = `uname -r`;
            my ($ma, $mi1, $mi2) = split("\\.", $verstr);
            ($mi2) = $mi2 =~ /(\d+)/;
            my $ver = $ma*10000 + $mi1*100 + $mi2;
            if ($ver < $minver) {
                disable('too-old-kernel', 'afalgeng');
            } else {
                push @{$config{engdirs}}, "afalg";
            }
        } else {
            disable('cross-compiling', 'afalgeng');
        }
    } else {
        disable('not-linux', 'afalgeng');
    }
}

unless ($disabled{devcryptoeng}) {
    if ($target =~ m/^BSD/) {
        my $maxver = 5*100 + 7;
        my $sysstr = `uname -s`;
        my $verstr = `uname -r`;
        $sysstr =~ s|\R$||;
        $verstr =~ s|\R$||;
        my ($ma, $mi, @rest) = split m|\.|, $verstr;
        my $ver = $ma*100 + $mi;
        if ($sysstr eq 'OpenBSD' && $ver >= $maxver) {
            disable('too-new-kernel', 'devcryptoeng');
        }
    }
}

# Get the extra flags used when building shared libraries and modules.  We
# do this late because some of them depend on %disabled.

# Make the flags to build DSOs the same as for shared libraries unless they
# are already defined
$target{module_cflags} = $target{shared_cflag} unless defined $target{module_cflags};
$target{module_cxxflags} = $target{shared_cxxflag} unless defined $target{module_cxxflags};
$target{module_ldflags} = $target{shared_ldflag} unless defined $target{module_ldflags};
{
    my $shared_info_pl =
        catfile(dirname($0), "Configurations", "shared-info.pl");
    my %shared_info = read_eval_file($shared_info_pl);
    push @{$target{_conf_fname_int}}, $shared_info_pl;
    my $si = $target{shared_target};
    while (ref $si ne "HASH") {
        last if ! defined $si;
        if (ref $si eq "CODE") {
            $si = $si->();
        } else {
            $si = $shared_info{$si};
        }
    }

    # Some of the 'shared_target' values don't have any entries in
    # %shared_info.  That's perfectly fine, AS LONG AS the build file
    # template knows how to handle this.  That is currently the case for
    # Windows and VMS.
    if (defined $si) {
        # Just as above, copy certain shared_* attributes to the corresponding
        # module_ attribute unless the latter is already defined
        $si->{module_cflags} = $si->{shared_cflag} unless defined $si->{module_cflags};
        $si->{module_cxxflags} = $si->{shared_cxxflag} unless defined $si->{module_cxxflags};
        $si->{module_ldflags} = $si->{shared_ldflag} unless defined $si->{module_ldflags};
        foreach (sort keys %$si) {
            $target{$_} = defined $target{$_}
                ? add($si->{$_})->($target{$_})
                : $si->{$_};
        }
    }
}

# ALL MODIFICATIONS TO %disabled, %config and %target MUST BE DONE FROM HERE ON

my %disabled_info = ();         # For configdata.pm
foreach my $what (sort keys %disabled) {
    $config{options} .= " no-$what";

    if (!grep { $what eq $_ } ( 'buildtest-c++', 'threads', 'shared', 'pic',
                                'dynamic-engine', 'makedepend',
                                'zlib-dynamic', 'zlib', 'sse2' )) {
        (my $WHAT = uc $what) =~ s|-|_|g;

        # Fix up C macro end names
        $WHAT = "RMD160" if $what eq "ripemd";

        # fix-up crypto/directory name(s)
        $what = "ripemd" if $what eq "rmd160";
        $what = "whrlpool" if $what eq "whirlpool";

        my $macro = $disabled_info{$what}->{macro} = "OPENSSL_NO_$WHAT";

        if ((grep { $what eq $_ } @{$config{sdirs}})
                && $what ne 'async' && $what ne 'err' && $what ne 'dso') {
            @{$config{sdirs}} = grep { $what ne $_} @{$config{sdirs}};
            $disabled_info{$what}->{skipped} = [ catdir('crypto', $what) ];

            if ($what ne 'engine') {
                push @{$config{openssl_algorithm_defines}}, $macro;
            } else {
                @{$config{dirs}} = grep !/^engines$/, @{$config{dirs}};
                push @{$disabled_info{engine}->{skipped}}, catdir('engines');
                push @{$config{openssl_other_defines}}, $macro;
            }
        } else {
            push @{$config{openssl_other_defines}}, $macro;
        }

    }
}

if ($disabled{"dynamic-engine"}) {
    push @{$config{openssl_other_defines}}, "OPENSSL_NO_DYNAMIC_ENGINE";
} else {
    push @{$config{openssl_other_defines}}, "OPENSSL_NO_STATIC_ENGINE";
}

# If we use the unified build, collect information from build.info files
my %unified_info = ();

my $buildinfo_debug = defined($ENV{CONFIGURE_DEBUG_BUILDINFO});
if ($builder eq "unified") {
    use with_fallback qw(Text::Template);

    sub cleandir {
        my $base = shift;
        my $dir = shift;
        my $relativeto = shift || ".";

        $dir = catdir($base,$dir) unless isabsolute($dir);

        # Make sure the directories we're building in exists
        mkpath($dir);

        my $res = abs2rel(absolutedir($dir), rel2abs($relativeto));
        #print STDERR "DEBUG[cleandir]: $dir , $base => $res\n";
        return $res;
    }

    sub cleanfile {
        my $base = shift;
        my $file = shift;
        my $relativeto = shift || ".";

        $file = catfile($base,$file) unless isabsolute($file);

        my $d = dirname($file);
        my $f = basename($file);

        # Make sure the directories we're building in exists
        mkpath($d);

        my $res = abs2rel(catfile(absolutedir($d), $f), rel2abs($relativeto));
        #print STDERR "DEBUG[cleanfile]: $d , $f => $res\n";
        return $res;
    }

    # Store the name of the template file we will build the build file from
    # in %config.  This may be useful for the build file itself.
    my @build_file_template_names =
        ( $builder_platform."-".$target{build_file}.".tmpl",
          $target{build_file}.".tmpl" );
    my @build_file_templates = ();

    # First, look in the user provided directory, if given
    if (defined env($local_config_envname)) {
        @build_file_templates =
            map {
                if ($^O eq 'VMS') {
                    # VMS environment variables are logical names,
                    # which can be used as is
                    $local_config_envname . ':' . $_;
                } else {
                    catfile(env($local_config_envname), $_);
                }
            }
            @build_file_template_names;
    }
    # Then, look in our standard directory
    push @build_file_templates,
        ( map { cleanfile($srcdir, catfile("Configurations", $_), $blddir) }
          @build_file_template_names );

    my $build_file_template;
    for $_ (@build_file_templates) {
        $build_file_template = $_;
        last if -f $build_file_template;

        $build_file_template = undef;
    }
    if (!defined $build_file_template) {
        die "*** Couldn't find any of:\n", join("\n", @build_file_templates), "\n";
    }
    $config{build_file_templates}
      = [ cleanfile($srcdir, catfile("Configurations", "common0.tmpl"),
                    $blddir),
          $build_file_template,
          cleanfile($srcdir, catfile("Configurations", "common.tmpl"),
                    $blddir) ];

    my @build_infos = ( [ ".", "build.info" ] );
    foreach (@{$config{dirs}}) {
        push @build_infos, [ $_, "build.info" ]
            if (-f catfile($srcdir, $_, "build.info"));
    }
    foreach (@{$config{sdirs}}) {
        push @build_infos, [ catdir("crypto", $_), "build.info" ]
            if (-f catfile($srcdir, "crypto", $_, "build.info"));
    }
    foreach (@{$config{engdirs}}) {
        push @build_infos, [ catdir("engines", $_), "build.info" ]
            if (-f catfile($srcdir, "engines", $_, "build.info"));
    }
    foreach (@{$config{tdirs}}) {
        push @build_infos, [ catdir("test", $_), "build.info" ]
            if (-f catfile($srcdir, "test", $_, "build.info"));
    }

    $config{build_infos} = [ ];

    my %ordinals = ();
    foreach (@build_infos) {
        my $sourced = catdir($srcdir, $_->[0]);
        my $buildd = catdir($blddir, $_->[0]);

        mkpath($buildd);

        my $f = $_->[1];
        # The basic things we're trying to build
        my @programs = ();
        my @programs_install = ();
        my @libraries = ();
        my @libraries_install = ();
        my @engines = ();
        my @engines_install = ();
        my @scripts = ();
        my @scripts_install = ();
        my @extra = ();
        my @overrides = ();
        my @intermediates = ();
        my @rawlines = ();

        my %sources = ();
        my %shared_sources = ();
        my %includes = ();
        my %depends = ();
        my %renames = ();
        my %sharednames = ();
        my %generate = ();

        # We want to detect configdata.pm in the source tree, so we
        # don't use it if the build tree is different.
        my $src_configdata = cleanfile($srcdir, "configdata.pm", $blddir);

        push @{$config{build_infos}}, catfile(abs2rel($sourced, $blddir), $f);
        my $template =
            Text::Template->new(TYPE => 'FILE',
                                SOURCE => catfile($sourced, $f),
                                PREPEND => qq{use lib "$FindBin::Bin/util/perl";});
        die "Something went wrong with $sourced/$f: $!\n" unless $template;
        my @text =
            split /^/m,
            $template->fill_in(HASH => { config => \%config,
                                         target => \%target,
                                         disabled => \%disabled,
                                         withargs => \%withargs,
                                         builddir => abs2rel($buildd, $blddir),
                                         sourcedir => abs2rel($sourced, $blddir),
                                         buildtop => abs2rel($blddir, $blddir),
                                         sourcetop => abs2rel($srcdir, $blddir) },
                               DELIMITERS => [ "{-", "-}" ]);

        # The top item of this stack has the following values
        # -2 positive already run and we found ELSE (following ELSIF should fail)
        # -1 positive already run (skip until ENDIF)
        # 0 negatives so far (if we're at a condition, check it)
        # 1 last was positive (don't skip lines until next ELSE, ELSIF or ENDIF)
        # 2 positive ELSE (following ELSIF should fail)
        my @skip = ();
        collect_information(
            collect_from_array([ @text ],
                               qr/\\$/ => sub { my $l1 = shift; my $l2 = shift;
                                                $l1 =~ s/\\$//; $l1.$l2 }),
            # Info we're looking for
            qr/^\s*IF\[((?:\\.|[^\\\]])*)\]\s*$/
            => sub {
                if (! @skip || $skip[$#skip] > 0) {
                    push @skip, !! $1;
                } else {
                    push @skip, -1;
                }
            },
            qr/^\s*ELSIF\[((?:\\.|[^\\\]])*)\]\s*$/
            => sub { die "ELSIF out of scope" if ! @skip;
                     die "ELSIF following ELSE" if abs($skip[$#skip]) == 2;
                     $skip[$#skip] = -1 if $skip[$#skip] != 0;
                     $skip[$#skip] = !! $1
                         if $skip[$#skip] == 0; },
            qr/^\s*ELSE\s*$/
            => sub { die "ELSE out of scope" if ! @skip;
                     $skip[$#skip] = -2 if $skip[$#skip] != 0;
                     $skip[$#skip] = 2 if $skip[$#skip] == 0; },
            qr/^\s*ENDIF\s*$/
            => sub { die "ENDIF out of scope" if ! @skip;
                     pop @skip; },
            qr/^\s*PROGRAMS(_NO_INST)?\s*=\s*(.*)\s*$/
            => sub {
                if (!@skip || $skip[$#skip] > 0) {
                    my $install = $1;
                    my @x = tokenize($2);
                    push @programs, @x;
                    push @programs_install, @x unless $install;
                }
            },
            qr/^\s*LIBS(_NO_INST)?\s*=\s*(.*)\s*$/
            => sub {
                if (!@skip || $skip[$#skip] > 0) {
                    my $install = $1;
                    my @x = tokenize($2);
                    push @libraries, @x;
                    push @libraries_install, @x unless $install;
                }
            },
            qr/^\s*ENGINES(_NO_INST)?\s*=\s*(.*)\s*$/
            => sub {
                if (!@skip || $skip[$#skip] > 0) {
                    my $install = $1;
                    my @x = tokenize($2);
                    push @engines, @x;
                    push @engines_install, @x unless $install;
                }
            },
            qr/^\s*SCRIPTS(_NO_INST)?\s*=\s*(.*)\s*$/
            => sub {
                if (!@skip || $skip[$#skip] > 0) {
                    my $install = $1;
                    my @x = tokenize($2);
                    push @scripts, @x;
                    push @scripts_install, @x unless $install;
                }
            },
            qr/^\s*EXTRA\s*=\s*(.*)\s*$/
            => sub { push @extra, tokenize($1)
                         if !@skip || $skip[$#skip] > 0 },
            qr/^\s*OVERRIDES\s*=\s*(.*)\s*$/
            => sub { push @overrides, tokenize($1)
                         if !@skip || $skip[$#skip] > 0 },

            qr/^\s*ORDINALS\[((?:\\.|[^\\\]])+)\]\s*=\s*(.*)\s*$/,
            => sub { push @{$ordinals{$1}}, tokenize($2)
                         if !@skip || $skip[$#skip] > 0 },
            qr/^\s*SOURCE\[((?:\\.|[^\\\]])+)\]\s*=\s*(.*)\s*$/
            => sub { push @{$sources{$1}}, tokenize($2)
                         if !@skip || $skip[$#skip] > 0 },
            qr/^\s*SHARED_SOURCE\[((?:\\.|[^\\\]])+)\]\s*=\s*(.*)\s*$/
            => sub { push @{$shared_sources{$1}}, tokenize($2)
                         if !@skip || $skip[$#skip] > 0 },
            qr/^\s*INCLUDE\[((?:\\.|[^\\\]])+)\]\s*=\s*(.*)\s*$/
            => sub { push @{$includes{$1}}, tokenize($2)
                         if !@skip || $skip[$#skip] > 0 },
            qr/^\s*DEPEND\[((?:\\.|[^\\\]])*)\]\s*=\s*(.*)\s*$/
            => sub { push @{$depends{$1}}, tokenize($2)
                         if !@skip || $skip[$#skip] > 0 },
            qr/^\s*GENERATE\[((?:\\.|[^\\\]])+)\]\s*=\s*(.*)\s*$/
            => sub { push @{$generate{$1}}, $2
                         if !@skip || $skip[$#skip] > 0 },
            qr/^\s*RENAME\[((?:\\.|[^\\\]])+)\]\s*=\s*(.*)\s*$/
            => sub { push @{$renames{$1}}, tokenize($2)
                         if !@skip || $skip[$#skip] > 0 },
            qr/^\s*SHARED_NAME\[((?:\\.|[^\\\]])+)\]\s*=\s*(.*)\s*$/
            => sub { push @{$sharednames{$1}}, tokenize($2)
                         if !@skip || $skip[$#skip] > 0 },
            qr/^\s*BEGINRAW\[((?:\\.|[^\\\]])+)\]\s*$/
            => sub {
                my $lineiterator = shift;
                my $target_kind = $1;
                while (defined $lineiterator->()) {
                    s|\R$||;
                    if (/^\s*ENDRAW\[((?:\\.|[^\\\]])+)\]\s*$/) {
                        die "ENDRAW doesn't match BEGINRAW"
                            if $1 ne $target_kind;
                        last;
                    }
                    next if @skip && $skip[$#skip] <= 0;
                    push @rawlines,  $_
                        if ($target_kind eq $target{build_file}
                            || $target_kind eq $target{build_file}."(".$builder_platform.")");
                }
            },
            qr/^\s*(?:#.*)?$/ => sub { },
            "OTHERWISE" => sub { die "Something wrong with this line:\n$_\nat $sourced/$f" },
            "BEFORE" => sub {
                if ($buildinfo_debug) {
                    print STDERR "DEBUG: Parsing ",join(" ", @_),"\n";
                    print STDERR "DEBUG: ... before parsing, skip stack is ",join(" ", map { int($_) } @skip),"\n";
                }
            },
            "AFTER" => sub {
                if ($buildinfo_debug) {
                    print STDERR "DEBUG: .... after parsing, skip stack is ",join(" ", map { int($_) } @skip),"\n";
                }
            },
            );
        die "runaway IF?" if (@skip);

        foreach (keys %renames) {
            die "$_ renamed to more than one thing: "
                ,join(" ", @{$renames{$_}}),"\n"
                if scalar @{$renames{$_}} > 1;
            my $dest = cleanfile($buildd, $_, $blddir);
            my $to = cleanfile($buildd, $renames{$_}->[0], $blddir);
            die "$dest renamed to more than one thing: "
                ,$unified_info{rename}->{$dest}, $to
                unless !defined($unified_info{rename}->{$dest})
                or $unified_info{rename}->{$dest} eq $to;
            $unified_info{rename}->{$dest} = $to;
        }

        foreach (@programs) {
            my $program = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$program}) {
                $program = $unified_info{rename}->{$program};
            }
            $unified_info{programs}->{$program} = 1;
        }

        foreach (@programs_install) {
            my $program = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$program}) {
                $program = $unified_info{rename}->{$program};
            }
            $unified_info{install}->{programs}->{$program} = 1;
        }

        foreach (@libraries) {
            my $library = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$library}) {
                $library = $unified_info{rename}->{$library};
            }
            $unified_info{libraries}->{$library} = 1;
        }

        foreach (@libraries_install) {
            my $library = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$library}) {
                $library = $unified_info{rename}->{$library};
            }
            $unified_info{install}->{libraries}->{$library} = 1;
        }

        die <<"EOF" if scalar @engines and !$config{dynamic_engines};
ENGINES can only be used if configured with 'dynamic-engine'.
This is usually a fault in a build.info file.
EOF
        foreach (@engines) {
            my $library = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$library}) {
                $library = $unified_info{rename}->{$library};
            }
            $unified_info{engines}->{$library} = 1;
        }

        foreach (@engines_install) {
            my $library = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$library}) {
                $library = $unified_info{rename}->{$library};
            }
            $unified_info{install}->{engines}->{$library} = 1;
        }

        foreach (@scripts) {
            my $script = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$script}) {
                $script = $unified_info{rename}->{$script};
            }
            $unified_info{scripts}->{$script} = 1;
        }

        foreach (@scripts_install) {
            my $script = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$script}) {
                $script = $unified_info{rename}->{$script};
            }
            $unified_info{install}->{scripts}->{$script} = 1;
        }

        foreach (@extra) {
            my $extra = cleanfile($buildd, $_, $blddir);
            $unified_info{extra}->{$extra} = 1;
        }

        foreach (@overrides) {
            my $override = cleanfile($buildd, $_, $blddir);
            $unified_info{overrides}->{$override} = 1;
        }

        push @{$unified_info{rawlines}}, @rawlines;

        unless ($disabled{shared}) {
            # Check sharednames.
            foreach (keys %sharednames) {
                my $dest = cleanfile($buildd, $_, $blddir);
                if ($unified_info{rename}->{$dest}) {
                    $dest = $unified_info{rename}->{$dest};
                }
                die "shared_name for $dest with multiple values: "
                    ,join(" ", @{$sharednames{$_}}),"\n"
                    if scalar @{$sharednames{$_}} > 1;
                my $to = cleanfile($buildd, $sharednames{$_}->[0], $blddir);
                die "shared_name found for a library $dest that isn't defined\n"
                    unless $unified_info{libraries}->{$dest};
                die "shared_name for $dest with multiple values: "
                    ,$unified_info{sharednames}->{$dest}, ", ", $to
                    unless !defined($unified_info{sharednames}->{$dest})
                    or $unified_info{sharednames}->{$dest} eq $to;
                $unified_info{sharednames}->{$dest} = $to;
            }

            # Additionally, we set up sharednames for libraries that don't
            # have any, as themselves.  Only for libraries that aren't
            # explicitly static.
            foreach (grep !/\.a$/, keys %{$unified_info{libraries}}) {
                if (!defined $unified_info{sharednames}->{$_}) {
                    $unified_info{sharednames}->{$_} = $_
                }
            }

            # Check that we haven't defined any library as both shared and
            # explicitly static.  That is forbidden.
            my @doubles = ();
            foreach (grep /\.a$/, keys %{$unified_info{libraries}}) {
                (my $l = $_) =~ s/\.a$//;
                push @doubles, $l if defined $unified_info{sharednames}->{$l};
            }
            die "these libraries are both explicitly static and shared:\n  ",
                join(" ", @doubles), "\n"
                if @doubles;
        }

        foreach (keys %sources) {
            my $dest = $_;
            my $ddest = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$ddest}) {
                $ddest = $unified_info{rename}->{$ddest};
            }
            foreach (@{$sources{$dest}}) {
                my $s = cleanfile($sourced, $_, $blddir);

                # If it isn't in the source tree, we assume it's generated
                # in the build tree
                if ($s eq $src_configdata || ! -f $s || $generate{$_}) {
                    $s = cleanfile($buildd, $_, $blddir);
                }
                # We recognise C++, C and asm files
                if ($s =~ /\.(cc|cpp|c|s|S)$/) {
                    my $o = $_;
                    $o =~ s/\.[csS]$/.o/; # C and assembler
                    $o =~ s/\.(cc|cpp)$/_cc.o/; # C++
                    $o = cleanfile($buildd, $o, $blddir);
                    $unified_info{sources}->{$ddest}->{$o} = 1;
                    $unified_info{sources}->{$o}->{$s} = 1;
                } elsif ($s =~ /\.rc$/) {
                    # We also recognise resource files
                    my $o = $_;
                    $o =~ s/\.rc$/.res/; # Resource configuration
                    my $o = cleanfile($buildd, $o, $blddir);
                    $unified_info{sources}->{$ddest}->{$o} = 1;
                    $unified_info{sources}->{$o}->{$s} = 1;
                } else {
                    $unified_info{sources}->{$ddest}->{$s} = 1;
                }
            }
        }

        foreach (keys %shared_sources) {
            my $dest = $_;
            my $ddest = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$ddest}) {
                $ddest = $unified_info{rename}->{$ddest};
            }
            foreach (@{$shared_sources{$dest}}) {
                my $s = cleanfile($sourced, $_, $blddir);

                # If it isn't in the source tree, we assume it's generated
                # in the build tree
                if ($s eq $src_configdata || ! -f $s || $generate{$_}) {
                    $s = cleanfile($buildd, $_, $blddir);
                }

                if ($s =~ /\.(cc|cpp|c|s|S)$/) {
                    # We recognise C++, C and asm files
                    my $o = $_;
                    $o =~ s/\.[csS]$/.o/; # C and assembler
                    $o =~ s/\.(cc|cpp)$/_cc.o/; # C++
                    $o = cleanfile($buildd, $o, $blddir);
                    $unified_info{shared_sources}->{$ddest}->{$o} = 1;
                    $unified_info{sources}->{$o}->{$s} = 1;
                } elsif ($s =~ /\.rc$/) {
                    # We also recognise resource files
                    my $o = $_;
                    $o =~ s/\.rc$/.res/; # Resource configuration
                    my $o = cleanfile($buildd, $o, $blddir);
                    $unified_info{shared_sources}->{$ddest}->{$o} = 1;
                    $unified_info{sources}->{$o}->{$s} = 1;
                } elsif ($s =~ /\.(def|map|opt)$/) {
                    # We also recognise .def / .map / .opt files
                    # We know they are generated files
                    my $def = cleanfile($buildd, $s, $blddir);
                    $unified_info{shared_sources}->{$ddest}->{$def} = 1;
                } else {
                    die "unrecognised source file type for shared library: $s\n";
                }
            }
        }

        foreach (keys %generate) {
            my $dest = $_;
            my $ddest = cleanfile($buildd, $_, $blddir);
            if ($unified_info{rename}->{$ddest}) {
                $ddest = $unified_info{rename}->{$ddest};
            }
            die "more than one generator for $dest: "
                    ,join(" ", @{$generate{$_}}),"\n"
                    if scalar @{$generate{$_}} > 1;
            my @generator = split /\s+/, $generate{$dest}->[0];
            $generator[0] = cleanfile($sourced, $generator[0], $blddir),
            $unified_info{generate}->{$ddest} = [ @generator ];
        }

        foreach (keys %depends) {
            my $dest = $_;
            my $ddest = $dest eq "" ? "" : cleanfile($sourced, $_, $blddir);

            # If the destination doesn't exist in source, it can only be
            # a generated file in the build tree.
            if ($ddest ne "" && ($ddest eq $src_configdata || ! -f $ddest)) {
                $ddest = cleanfile($buildd, $_, $blddir);
                if ($unified_info{rename}->{$ddest}) {
                    $ddest = $unified_info{rename}->{$ddest};
                }
            }
            foreach (@{$depends{$dest}}) {
                my $d = cleanfile($sourced, $_, $blddir);

                # If we know it's generated, or assume it is because we can't
                # find it in the source tree, we set file we depend on to be
                # in the build tree rather than the source tree, and assume
                # and that there are lines to build it in a BEGINRAW..ENDRAW
                # section or in the Makefile template.
                if ($d eq $src_configdata
                    || ! -f $d
                    || (grep { $d eq $_ }
                        map { cleanfile($srcdir, $_, $blddir) }
                        grep { /\.h$/ } keys %{$unified_info{generate}})) {
                    $d = cleanfile($buildd, $_, $blddir);
                }
                # Take note if the file to depend on is being renamed
                # Take extra care with files ending with .a, they should
                # be treated without that extension, and the extension
                # should be added back after treatment.
                $d =~ /(\.a)?$/;
                my $e = $1 // "";
                $d = $`;
                if ($unified_info{rename}->{$d}) {
                    $d = $unified_info{rename}->{$d};
                }
                $d .= $e;
                $unified_info{depends}->{$ddest}->{$d} = 1;
            }
        }

        foreach (keys %includes) {
            my $dest = $_;
            my $ddest = cleanfile($sourced, $_, $blddir);

            # If the destination doesn't exist in source, it can only be
            # a generated file in the build tree.
            if ($ddest eq $src_configdata || ! -f $ddest) {
                $ddest = cleanfile($buildd, $_, $blddir);
                if ($unified_info{rename}->{$ddest}) {
                    $ddest = $unified_info{rename}->{$ddest};
                }
            }
            foreach (@{$includes{$dest}}) {
                my $is = cleandir($sourced, $_, $blddir);
                my $ib = cleandir($buildd, $_, $blddir);
                push @{$unified_info{includes}->{$ddest}->{source}}, $is
                    unless grep { $_ eq $is } @{$unified_info{includes}->{$ddest}->{source}};
                push @{$unified_info{includes}->{$ddest}->{build}}, $ib
                    unless grep { $_ eq $ib } @{$unified_info{includes}->{$ddest}->{build}};
            }
        }
    }

    my $ordinals_text = join(', ', sort keys %ordinals);
    warn <<"EOF" if $ordinals_text;

WARNING: ORDINALS were specified for $ordinals_text
They are ignored and should be replaced with a combination of GENERATE,
DEPEND and SHARED_SOURCE.
EOF

    # Massage the result

    # If the user configured no-shared, we allow no shared sources
    if ($disabled{shared}) {
        foreach (keys %{$unified_info{shared_sources}}) {
            foreach (keys %{$unified_info{shared_sources}->{$_}}) {
                delete $unified_info{sources}->{$_};
            }
        }
        $unified_info{shared_sources} = {};
    }

    # If we depend on a header file or a perl module, add an inclusion of
    # its directory to allow smoothe inclusion
    foreach my $dest (keys %{$unified_info{depends}}) {
        next if $dest eq "";
        foreach my $d (keys %{$unified_info{depends}->{$dest}}) {
            next unless $d =~ /\.(h|pm)$/;
            my $i = dirname($d);
            my $spot =
                $d eq "configdata.pm" || defined($unified_info{generate}->{$d})
                ? 'build' : 'source';
            push @{$unified_info{includes}->{$dest}->{$spot}}, $i
                unless grep { $_ eq $i } @{$unified_info{includes}->{$dest}->{$spot}};
        }
    }

    # Trickle down includes placed on libraries, engines and programs to
    # their sources (i.e. object files)
    foreach my $dest (keys %{$unified_info{engines}},
                      keys %{$unified_info{libraries}},
                      keys %{$unified_info{programs}}) {
        foreach my $k (("source", "build")) {
            next unless defined($unified_info{includes}->{$dest}->{$k});
            my @incs = reverse @{$unified_info{includes}->{$dest}->{$k}};
            foreach my $obj (grep /\.o$/,
                             (keys %{$unified_info{sources}->{$dest} // {}},
                              keys %{$unified_info{shared_sources}->{$dest} // {}})) {
                foreach my $inc (@incs) {
                    unshift @{$unified_info{includes}->{$obj}->{$k}}, $inc
                        unless grep { $_ eq $inc } @{$unified_info{includes}->{$obj}->{$k}};
                }
            }
        }
        delete $unified_info{includes}->{$dest};
    }

    ### Make unified_info a bit more efficient
    # One level structures
    foreach (("programs", "libraries", "engines", "scripts", "extra", "overrides")) {
        $unified_info{$_} = [ sort keys %{$unified_info{$_}} ];
    }
    # Two level structures
    foreach my $l1 (("install", "sources", "shared_sources", "ldadd", "depends")) {
        foreach my $l2 (sort keys %{$unified_info{$l1}}) {
            $unified_info{$l1}->{$l2} =
                [ sort keys %{$unified_info{$l1}->{$l2}} ];
        }
    }
    # Includes
    foreach my $dest (sort keys %{$unified_info{includes}}) {
        if (defined($unified_info{includes}->{$dest}->{build})) {
            my @source_includes = ();
            @source_includes = ( @{$unified_info{includes}->{$dest}->{source}} )
                if defined($unified_info{includes}->{$dest}->{source});
            $unified_info{includes}->{$dest} =
                [ @{$unified_info{includes}->{$dest}->{build}} ];
            foreach my $inc (@source_includes) {
                push @{$unified_info{includes}->{$dest}}, $inc
                    unless grep { $_ eq $inc } @{$unified_info{includes}->{$dest}};
            }
        } else {
            $unified_info{includes}->{$dest} =
                [ @{$unified_info{includes}->{$dest}->{source}} ];
        }
    }

    # For convenience collect information regarding directories where
    # files are generated, those generated files and the end product
    # they end up in where applicable.  Then, add build rules for those
    # directories
    my %loopinfo = ( "lib" => [ @{$unified_info{libraries}} ],
                     "dso" => [ @{$unified_info{engines}} ],
                     "bin" => [ @{$unified_info{programs}} ],
                     "script" => [ @{$unified_info{scripts}} ] );
    foreach my $type (keys %loopinfo) {
        foreach my $product (@{$loopinfo{$type}}) {
            my %dirs = ();
            my $pd = dirname($product);

            foreach (@{$unified_info{sources}->{$product} // []},
                     @{$unified_info{shared_sources}->{$product} // []}) {
                my $d = dirname($_);

                # We don't want to create targets for source directories
                # when building out of source
                next if ($config{sourcedir} ne $config{builddir}
                             && $d =~ m|^\Q$config{sourcedir}\E|);
                # We already have a "test" target, and the current directory
                # is just silly to make a target for
                next if $d eq "test" || $d eq ".";

                $dirs{$d} = 1;
                push @{$unified_info{dirinfo}->{$d}->{deps}}, $_
                    if $d ne $pd;
            }
            foreach (keys %dirs) {
                push @{$unified_info{dirinfo}->{$_}->{products}->{$type}},
                    $product;
            }
        }
    }
}

# For the schemes that need it, we provide the old *_obj configs
# from the *_asm_obj ones
foreach (grep /_(asm|aux)_src$/, keys %target) {
    my $src = $_;
    (my $obj = $_) =~ s/_(asm|aux)_src$/_obj/;
    $target{$obj} = $target{$src};
    $target{$obj} =~ s/\.[csS]\b/.o/g; # C and assembler
    $target{$obj} =~ s/\.(cc|cpp)\b/_cc.o/g; # C++
}

# Write down our configuration where it fits #########################

print "Creating configdata.pm\n";
open(OUT,">configdata.pm") || die "unable to create configdata.pm: $!\n";
print OUT <<"EOF";
#! $config{HASHBANGPERL}

package configdata;

use strict;
use warnings;

use Exporter;
#use vars qw(\@ISA \@EXPORT);
our \@ISA = qw(Exporter);
our \@EXPORT = qw(\%config \%target \%disabled \%withargs \%unified_info \@disablables);

EOF
print OUT "our %config = (\n";
foreach (sort keys %config) {
    if (ref($config{$_}) eq "ARRAY") {
        print OUT "  ", $_, " => [ ", join(", ",
                                           map { quotify("perl", $_) }
                                           @{$config{$_}}), " ],\n";
    } elsif (ref($config{$_}) eq "HASH") {
        print OUT "  ", $_, " => {";
        if (scalar keys %{$config{$_}} > 0) {
            print OUT "\n";
            foreach my $key (sort keys %{$config{$_}}) {
                print OUT "      ",
                    join(" => ",
                         quotify("perl", $key),
                         defined $config{$_}->{$key}
                             ? quotify("perl", $config{$_}->{$key})
                             : "undef");
                print OUT ",\n";
            }
            print OUT "  ";
        }
        print OUT "},\n";
    } else {
        print OUT "  ", $_, " => ", quotify("perl", $config{$_}), ",\n"
    }
}
print OUT <<"EOF";
);

EOF
print OUT "our %target = (\n";
foreach (sort keys %target) {
    if (ref($target{$_}) eq "ARRAY") {
        print OUT "  ", $_, " => [ ", join(", ",
                                           map { quotify("perl", $_) }
                                           @{$target{$_}}), " ],\n";
    } else {
        print OUT "  ", $_, " => ", quotify("perl", $target{$_}), ",\n"
    }
}
print OUT <<"EOF";
);

EOF
print OUT "our \%available_protocols = (\n";
print OUT "  tls => [ ", join(", ", map { quotify("perl", $_) } @tls), " ],\n";
print OUT "  dtls => [ ", join(", ", map { quotify("perl", $_) } @dtls), " ],\n";
print OUT <<"EOF";
);

EOF
print OUT "our \@disablables = (\n";
foreach (@disablables) {
    print OUT "  ", quotify("perl", $_), ",\n";
}
print OUT <<"EOF";
);

EOF
print OUT "our \%disabled = (\n";
foreach (sort keys %disabled) {
    print OUT "  ", quotify("perl", $_), " => ", quotify("perl", $disabled{$_}), ",\n";
}
print OUT <<"EOF";
);

EOF
print OUT "our %withargs = (\n";
foreach (sort keys %withargs) {
    if (ref($withargs{$_}) eq "ARRAY") {
        print OUT "  ", $_, " => [ ", join(", ",
                                           map { quotify("perl", $_) }
                                           @{$withargs{$_}}), " ],\n";
    } else {
        print OUT "  ", $_, " => ", quotify("perl", $withargs{$_}), ",\n"
    }
}
print OUT <<"EOF";
);

EOF
if ($builder eq "unified") {
    my $recurse;
    $recurse = sub {
        my $indent = shift;
        foreach (@_) {
            if (ref $_ eq "ARRAY") {
                print OUT " "x$indent, "[\n";
                foreach (@$_) {
                    $recurse->($indent + 4, $_);
                }
                print OUT " "x$indent, "],\n";
            } elsif (ref $_ eq "HASH") {
                my %h = %$_;
                print OUT " "x$indent, "{\n";
                foreach (sort keys %h) {
                    if (ref $h{$_} eq "") {
                        print OUT " "x($indent + 4), quotify("perl", $_), " => ", quotify("perl", $h{$_}), ",\n";
                    } else {
                        print OUT " "x($indent + 4), quotify("perl", $_), " =>\n";
                        $recurse->($indent + 8, $h{$_});
                    }
                }
                print OUT " "x$indent, "},\n";
            } else {
                print OUT " "x$indent, quotify("perl", $_), ",\n";
            }
        }
    };
    print OUT "our %unified_info = (\n";
    foreach (sort keys %unified_info) {
        if (ref $unified_info{$_} eq "") {
            print OUT " "x4, quotify("perl", $_), " => ", quotify("perl", $unified_info{$_}), ",\n";
        } else {
            print OUT " "x4, quotify("perl", $_), " =>\n";
            $recurse->(8, $unified_info{$_});
        }
    }
    print OUT <<"EOF";
);

EOF
}
print OUT
    "# The following data is only used when this files is use as a script\n";
print OUT "my \@makevars = (\n";
foreach (sort keys %user) {
    print OUT "    '",$_,"',\n";
}
print OUT ");\n";
print OUT "my \%disabled_info = (\n";
foreach my $what (sort keys %disabled_info) {
    print OUT "    '$what' => {\n";
    foreach my $info (sort keys %{$disabled_info{$what}}) {
        if (ref $disabled_info{$what}->{$info} eq 'ARRAY') {
            print OUT "        $info => [ ",
                join(', ', map { "'$_'" } @{$disabled_info{$what}->{$info}}),
                " ],\n";
        } else {
            print OUT "        $info => '", $disabled_info{$what}->{$info},
                "',\n";
        }
    }
    print OUT "    },\n";
}
print OUT ");\n";
print OUT 'my @user_crossable = qw( ', join (' ', @user_crossable), " );\n";
print OUT << 'EOF';
# If run directly, we can give some answers, and even reconfigure
unless (caller) {
    use Getopt::Long;
    use File::Spec::Functions;
    use File::Basename;
    use Pod::Usage;

    my $here = dirname($0);

    my $dump = undef;
    my $cmdline = undef;
    my $options = undef;
    my $target = undef;
    my $envvars = undef;
    my $makevars = undef;
    my $buildparams = undef;
    my $reconf = undef;
    my $verbose = undef;
    my $help = undef;
    my $man = undef;
    GetOptions('dump|d'                 => \$dump,
               'command-line|c'         => \$cmdline,
               'options|o'              => \$options,
               'target|t'               => \$target,
               'environment|e'          => \$envvars,
               'make-variables|m'       => \$makevars,
               'build-parameters|b'     => \$buildparams,
               'reconfigure|reconf|r'   => \$reconf,
               'verbose|v'              => \$verbose,
               'help'                   => \$help,
               'man'                    => \$man)
        or die "Errors in command line arguments\n";

    unless ($dump || $cmdline || $options || $target || $envvars || $makevars
            || $buildparams || $reconf || $verbose || $help || $man) {
        print STDERR <<"_____";
You must give at least one option.
For more information, do '$0 --help'
_____
        exit(2);
    }

    if ($help) {
        pod2usage(-exitval => 0,
                  -verbose => 1);
    }
    if ($man) {
        pod2usage(-exitval => 0,
                  -verbose => 2);
    }
    if ($dump || $cmdline) {
        print "\nCommand line (with current working directory = $here):\n\n";
        print '    ',join(' ',
                          $config{PERL},
                          catfile($config{sourcedir}, 'Configure'),
                          @{$config{perlargv}}), "\n";
        print "\nPerl information:\n\n";
        print '    ',$config{perl_cmd},"\n";
        print '    ',$config{perl_version},' for ',$config{perl_archname},"\n";
    }
    if ($dump || $options) {
        my $longest = 0;
        my $longest2 = 0;
        foreach my $what (@disablables) {
            $longest = length($what) if $longest < length($what);
            $longest2 = length($disabled{$what})
                if $disabled{$what} && $longest2 < length($disabled{$what});
        }
        print "\nEnabled features:\n\n";
        foreach my $what (@disablables) {
            print "    $what\n" unless $disabled{$what};
        }
        print "\nDisabled features:\n\n";
        foreach my $what (@disablables) {
            if ($disabled{$what}) {
                print "    $what", ' ' x ($longest - length($what) + 1),
                    "[$disabled{$what}]", ' ' x ($longest2 - length($disabled{$what}) + 1);
                print $disabled_info{$what}->{macro}
                    if $disabled_info{$what}->{macro};
                print ' (skip ',
                    join(', ', @{$disabled_info{$what}->{skipped}}),
                    ')'
                    if $disabled_info{$what}->{skipped};
                print "\n";
            }
        }
    }
    if ($dump || $target) {
        print "\nConfig target attributes:\n\n";
        foreach (sort keys %target) {
            next if $_ =~ m|^_| || $_ eq 'template';
            my $quotify = sub {
                map { (my $x = $_) =~ s|([\\\$\@"])|\\$1|g; "\"$x\""} @_;
            };
            print '    ', $_, ' => ';
            if (ref($target{$_}) eq "ARRAY") {
                print '[ ', join(', ', $quotify->(@{$target{$_}})), " ],\n";
            } else {
                print $quotify->($target{$_}), ",\n"
            }
        }
    }
    if ($dump || $envvars) {
        print "\nRecorded environment:\n\n";
        foreach (sort keys %{$config{perlenv}}) {
            print '    ',$_,' = ',($config{perlenv}->{$_} || ''),"\n";
        }
    }
    if ($dump || $makevars) {
        print "\nMakevars:\n\n";
        foreach my $var (@makevars) {
            my $prefix = '';
            $prefix = $config{CROSS_COMPILE}
                if grep { $var eq $_ } @user_crossable;
            $prefix //= '';
            print '    ',$var,' ' x (16 - length $var),'= ',
                (ref $config{$var} eq 'ARRAY'
                 ? join(' ', @{$config{$var}})
                 : $prefix.$config{$var}),
                "\n"
                if defined $config{$var};
        }

        my @buildfile = ($config{builddir}, $config{build_file});
        unshift @buildfile, $here
            unless file_name_is_absolute($config{builddir});
        my $buildfile = canonpath(catdir(@buildfile));
        print <<"_____";

NOTE: These variables only represent the configuration view.  The build file
template may have processed these variables further, please have a look at the
build file for more exact data:
    $buildfile
_____
    }
    if ($dump || $buildparams) {
        my @buildfile = ($config{builddir}, $config{build_file});
        unshift @buildfile, $here
            unless file_name_is_absolute($config{builddir});
        print "\nbuild file:\n\n";
        print "    ", canonpath(catfile(@buildfile)),"\n";

        print "\nbuild file templates:\n\n";
        foreach (@{$config{build_file_templates}}) {
            my @tmpl = ($_);
            unshift @tmpl, $here
                unless file_name_is_absolute($config{sourcedir});
            print '    ',canonpath(catfile(@tmpl)),"\n";
        }
    }
    if ($reconf) {
        if ($verbose) {
            print 'Reconfiguring with: ', join(' ',@{$config{perlargv}}), "\n";
            foreach (sort keys %{$config{perlenv}}) {
                print '    ',$_,' = ',($config{perlenv}->{$_} || ""),"\n";
            }
        }

        chdir $here;
        exec $^X,catfile($config{sourcedir}, 'Configure'),'reconf';
    }
}

1;

__END__

=head1 NAME

configdata.pm - configuration data for OpenSSL builds

=head1 SYNOPSIS

Interactive:

  perl configdata.pm [options]

As data bank module:

  use configdata;

=head1 DESCRIPTION

This module can be used in two modes, interactively and as a module containing
all the data recorded by OpenSSL's Configure script.

When used interactively, simply run it as any perl script, with at least one
option, and you will get the information you ask for.  See L</OPTIONS> below.

When loaded as a module, you get a few databanks with useful information to
perform build related tasks.  The databanks are:

    %config             Configured things.
    %target             The OpenSSL config target with all inheritances
                        resolved.
    %disabled           The features that are disabled.
    @disablables        The list of features that can be disabled.
    %withargs           All data given through --with-THING options.
    %unified_info       All information that was computed from the build.info
                        files.

=head1 OPTIONS

=over 4

=item B<--help>

Print a brief help message and exit.

=item B<--man>

Print the manual page and exit.

=item B<--dump> | B<-d>

Print all relevant configuration data.  This is equivalent to B<--command-line>
B<--options> B<--target> B<--environment> B<--make-variables>
B<--build-parameters>.

=item B<--command-line> | B<-c>

Print the current configuration command line.

=item B<--options> | B<-o>

Print the features, both enabled and disabled, and display defined macro and
skipped directories where applicable.

=item B<--target> | B<-t>

Print the config attributes for this config target.

=item B<--environment> | B<-e>

Print the environment variables and their values at the time of configuration.

=item B<--make-variables> | B<-m>

Print the main make variables generated in the current configuration

=item B<--build-parameters> | B<-b>

Print the build parameters, i.e. build file and build file templates.

=item B<--reconfigure> | B<--reconf> | B<-r>

Redo the configuration.

=item B<--verbose> | B<-v>

Verbose output.

=back

=cut

EOF
close(OUT);
if ($builder_platform eq 'unix') {
    my $mode = (0755 & ~umask);
    chmod $mode, 'configdata.pm'
        or warn sprintf("WARNING: Couldn't change mode for 'configdata.pm' to 0%03o: %s\n",$mode,$!);
}

my %builders = (
    unified => sub {
        print 'Creating ',$target{build_file},"\n";
        run_dofile(catfile($blddir, $target{build_file}),
                   @{$config{build_file_templates}});
    },
    );

$builders{$builder}->($builder_platform, @builder_opts);

$SIG{__DIE__} = $orig_death_handler;

print <<"EOF" if ($disabled{threads} eq "unavailable");

The library could not be configured for supporting multi-threaded
applications as the compiler options required on this system are not known.
See file INSTALL for details if you need multi-threading.
EOF

print <<"EOF" if ($no_shared_warn);

The options 'shared', 'pic' and 'dynamic-engine' aren't supported on this
platform, so we will pretend you gave the option 'no-pic', which also disables
'shared' and 'dynamic-engine'.  If you know how to implement shared libraries
or position independent code, please let us know (but please first make sure
you have tried with a current version of OpenSSL).
EOF

print <<"EOF";

**********************************************************************
***                                                                ***
***   OpenSSL has been successfully configured                     ***
***                                                                ***
***   If you encounter a problem while building, please open an    ***
***   issue on GitHub <https://github.com/openssl/openssl/issues>  ***
***   and include the output from the following command:           ***
***                                                                ***
***       perl configdata.pm --dump                                ***
***                                                                ***
***   (If you are new to OpenSSL, you might want to consult the    ***
***   'Troubleshooting' section in the INSTALL file first)         ***
***                                                                ***
**********************************************************************
EOF

exit(0);

######################################################################
#
# Helpers and utility functions
#

# Death handler, to print a helpful message in case of failure #######
#
sub death_handler {
    die @_ if $^S;              # To prevent the added message in eval blocks
    my $build_file = $target{build_file} // "build file";
    my @message = ( <<"_____", @_ );

Failure!  $build_file wasn't produced.
Please read INSTALL and associated NOTES files.  You may also have to look over
your available compiler tool chain or change your configuration.

_____

    # Dying is terminal, so it's ok to reset the signal handler here.
    $SIG{__DIE__} = $orig_death_handler;
    die @message;
}

# Configuration file reading #########################################

# Note: All of the helper functions are for lazy evaluation.  They all
# return a CODE ref, which will return the intended value when evaluated.
# Thus, whenever there's mention of a returned value, it's about that
# intended value.

# Helper function to implement conditional inheritance depending on the
# value of $disabled{asm}.  Used in inherit_from values as follows:
#
#      inherit_from => [ "template", asm("asm_tmpl") ]
#
sub asm {
    my @x = @_;
    sub {
        $disabled{asm} ? () : @x;
    }
}

# Helper function to implement conditional value variants, with a default
# plus additional values based on the value of $config{build_type}.
# Arguments are given in hash table form:
#
#       picker(default => "Basic string: ",
#              debug   => "debug",
#              release => "release")
#
# When configuring with --debug, the resulting string will be
# "Basic string: debug", and when not, it will be "Basic string: release"
#
# This can be used to create variants of sets of flags according to the
# build type:
#
#       cflags => picker(default => "-Wall",
#                        debug   => "-g -O0",
#                        release => "-O3")
#
sub picker {
    my %opts = @_;
    return sub { add($opts{default} || (),
                     $opts{$config{build_type}} || ())->(); }
}

# Helper function to combine several values of different types into one.
# This is useful if you want to combine a string with the result of a
# lazy function, such as:
#
#       cflags => combine("-Wall", sub { $disabled{zlib} ? () : "-DZLIB" })
#
sub combine {
    my @stuff = @_;
    return sub { add(@stuff)->(); }
}

# Helper function to implement conditional values depending on the value
# of $disabled{threads}.  Can be used as follows:
#
#       cflags => combine("-Wall", threads("-pthread"))
#
sub threads {
    my @flags = @_;
    return sub { add($disabled{threads} ? () : @flags)->(); }
}

sub shared {
    my @flags = @_;
    return sub { add($disabled{shared} ? () : @flags)->(); }
}

our $add_called = 0;
# Helper function to implement adding values to already existing configuration
# values.  It handles elements that are ARRAYs, CODEs and scalars
sub _add {
    my $separator = shift;

    # If there's any ARRAY in the collection of values OR the separator
    # is undef, we will return an ARRAY of combined values, otherwise a
    # string of joined values with $separator as the separator.
    my $found_array = !defined($separator);

    my @values =
        map {
            my $res = $_;
            while (ref($res) eq "CODE") {
                $res = $res->();
            }
            if (defined($res)) {
                if (ref($res) eq "ARRAY") {
                    $found_array = 1;
                    @$res;
                } else {
                    $res;
                }
            } else {
                ();
            }
    } (@_);

    $add_called = 1;

    if ($found_array) {
        [ @values ];
    } else {
        join($separator, grep { defined($_) && $_ ne "" } @values);
    }
}
sub add_before {
    my $separator = " ";
    if (ref($_[$#_]) eq "HASH") {
        my $opts = pop;
        $separator = $opts->{separator};
    }
    my @x = @_;
    sub { _add($separator, @x, @_) };
}
sub add {
    my $separator = " ";
    if (ref($_[$#_]) eq "HASH") {
        my $opts = pop;
        $separator = $opts->{separator};
    }
    my @x = @_;
    sub { _add($separator, @_, @x) };
}

sub read_eval_file {
    my $fname = shift;
    my $content;
    my @result;

    open F, "< $fname" or die "Can't open '$fname': $!\n";
    {
        undef local $/;
        $content = <F>;
    }
    close F;
    {
        local $@;

        @result = ( eval $content );
        warn $@ if $@;
    }
    return wantarray ? @result : $result[0];
}

# configuration reader, evaluates the input file as a perl script and expects
# it to fill %targets with target configurations.  Those are then added to
# %table.
sub read_config {
    my $fname = shift;
    my %targets;

    {
        # Protect certain tables from tampering
        local %table = ();

        %targets = read_eval_file($fname);
    }
    my %preexisting = ();
    foreach (sort keys %targets) {
        $preexisting{$_} = 1 if $table{$_};
    }
    die <<"EOF",
The following config targets from $fname
shadow pre-existing config targets with the same name:
EOF
        map { "  $_\n" } sort keys %preexisting
        if %preexisting;


    # For each target, check that it's configured with a hash table.
    foreach (keys %targets) {
        if (ref($targets{$_}) ne "HASH") {
            if (ref($targets{$_}) eq "") {
                warn "Deprecated target configuration for $_, ignoring...\n";
            } else {
                warn "Misconfigured target configuration for $_ (should be a hash table), ignoring...\n";
            }
            delete $targets{$_};
        } else {
            $targets{$_}->{_conf_fname_int} = add([ $fname ]);
        }
    }

    %table = (%table, %targets);

}

# configuration resolver.  Will only resolve all the lazy evaluation
# codeblocks for the chosen target and all those it inherits from,
# recursively
sub resolve_config {
    my $target = shift;
    my @breadcrumbs = @_;

#    my $extra_checks = defined($ENV{CONFIGURE_EXTRA_CHECKS});

    if (grep { $_ eq $target } @breadcrumbs) {
        die "inherit_from loop!  target backtrace:\n  "
            ,$target,"\n  ",join("\n  ", @breadcrumbs),"\n";
    }

    if (!defined($table{$target})) {
        warn "Warning! target $target doesn't exist!\n";
        return ();
    }
    # Recurse through all inheritances.  They will be resolved on the
    # fly, so when this operation is done, they will all just be a
    # bunch of attributes with string values.
    # What we get here, though, are keys with references to lists of
    # the combined values of them all.  We will deal with lists after
    # this stage is done.
    my %combined_inheritance = ();
    if ($table{$target}->{inherit_from}) {
        my @inherit_from =
            map { ref($_) eq "CODE" ? $_->() : $_ } @{$table{$target}->{inherit_from}};
        foreach (@inherit_from) {
            my %inherited_config = resolve_config($_, $target, @breadcrumbs);

            # 'template' is a marker that's considered private to
            # the config that had it.
            delete $inherited_config{template};

            foreach (keys %inherited_config) {
                if (!$combined_inheritance{$_}) {
                    $combined_inheritance{$_} = [];
                }
                push @{$combined_inheritance{$_}}, $inherited_config{$_};
            }
        }
    }

    # We won't need inherit_from in this target any more, since we've
    # resolved all the inheritances that lead to this
    delete $table{$target}->{inherit_from};

    # Now is the time to deal with those lists.  Here's the place to
    # decide what shall be done with those lists, all based on the
    # values of the target we're currently dealing with.
    # - If a value is a coderef, it will be executed with the list of
    #   inherited values as arguments.
    # - If the corresponding key doesn't have a value at all or is the
    #   empty string, the inherited value list will be run through the
    #   default combiner (below), and the result becomes this target's
    #   value.
    # - Otherwise, this target's value is assumed to be a string that
    #   will simply override the inherited list of values.
    my $default_combiner = add();

    my %all_keys =
        map { $_ => 1 } (keys %combined_inheritance,
                         keys %{$table{$target}});

    sub process_values {
        my $object    = shift;
        my $inherited = shift;  # Always a [ list ]
        my $target    = shift;
        my $entry     = shift;

        $add_called = 0;

        while(ref($object) eq "CODE") {
            $object = $object->(@$inherited);
        }
        if (!defined($object)) {
            return ();
        }
        elsif (ref($object) eq "ARRAY") {
            local $add_called;  # To make sure recursive calls don't affect it
            return [ map { process_values($_, $inherited, $target, $entry) }
                     @$object ];
        } elsif (ref($object) eq "") {
            return $object;
        } else {
            die "cannot handle reference type ",ref($object)
                ," found in target ",$target," -> ",$entry,"\n";
        }
    }

    foreach (sort keys %all_keys) {
        my $previous = $combined_inheritance{$_};

        # Current target doesn't have a value for the current key?
        # Assign it the default combiner, the rest of this loop body
        # will handle it just like any other coderef.
        if (!exists $table{$target}->{$_}) {
            $table{$target}->{$_} = $default_combiner;
        }

        $table{$target}->{$_} = process_values($table{$target}->{$_},
                                               $combined_inheritance{$_},
                                               $target, $_);
        unless(defined($table{$target}->{$_})) {
            delete $table{$target}->{$_};
        }
#        if ($extra_checks &&
#            $previous && !($add_called ||  $previous ~~ $table{$target}->{$_})) {
#            warn "$_ got replaced in $target\n";
#        }
    }

    # Finally done, return the result.
    return %{$table{$target}};
}

sub usage
        {
        print STDERR $usage;
        print STDERR "\npick os/compiler from:\n";
        my $j=0;
        my $i;
        my $k=0;
        foreach $i (sort keys %table)
                {
                next if $table{$i}->{template};
                next if $i =~ /^debug/;
                $k += length($i) + 1;
                if ($k > 78)
                        {
                        print STDERR "\n";
                        $k=length($i);
                        }
                print STDERR $i . " ";
                }
        foreach $i (sort keys %table)
                {
                next if $table{$i}->{template};
                next if $i !~ /^debug/;
                $k += length($i) + 1;
                if ($k > 78)
                        {
                        print STDERR "\n";
                        $k=length($i);
                        }
                print STDERR $i . " ";
                }
        print STDERR "\n\nNOTE: If in doubt, on Unix-ish systems use './config'.\n";
        exit(1);
        }

sub run_dofile
{
    my $out = shift;
    my @templates = @_;

    unlink $out || warn "Can't remove $out, $!"
        if -f $out;
    foreach (@templates) {
        die "Can't open $_, $!" unless -f $_;
    }
    my $perlcmd = (quotify("maybeshell", $config{PERL}))[0];
    my $cmd = "$perlcmd \"-I.\" \"-Mconfigdata\" \"$dofile\" -o\"Configure\" \"".join("\" \"",@templates)."\" > \"$out.new\"";
    #print STDERR "DEBUG[run_dofile]: \$cmd = $cmd\n";
    system($cmd);
    exit 1 if $? != 0;
    rename("$out.new", $out) || die "Can't rename $out.new, $!";
}

sub compiler_predefined {
    state %predefined;
    my $cc = shift;

    return () if $^O eq 'VMS';

    die 'compiler_predefined called without a compiler command'
        unless $cc;

    if (! $predefined{$cc}) {

        $predefined{$cc} = {};

        # collect compiler pre-defines from gcc or gcc-alike...
        open(PIPE, "$cc -dM -E -x c /dev/null 2>&1 |");
        while (my $l = <PIPE>) {
            $l =~ m/^#define\s+(\w+(?:\(\w+\))?)(?:\s+(.+))?/ or last;
            $predefined{$cc}->{$1} = $2 // '';
        }
        close(PIPE);
    }

    return %{$predefined{$cc}};
}

sub which
{
    my ($name)=@_;

    if (eval { require IPC::Cmd; 1; }) {
        IPC::Cmd->import();
        return scalar IPC::Cmd::can_run($name);
    } else {
        # if there is $directories component in splitpath,
        # then it's not something to test with $PATH...
        return $name if (File::Spec->splitpath($name))[1];

        foreach (File::Spec->path()) {
            my $fullpath = catfile($_, "$name$target{exe_extension}");
            if (-f $fullpath and -x $fullpath) {
                return $fullpath;
            }
        }
    }
}

sub env
{
    my $name = shift;
    my %opts = @_;

    unless ($opts{cacheonly}) {
        # Note that if $ENV{$name} doesn't exist or is undefined,
        # $config{perlenv}->{$name} will be created with the value
        # undef.  This is intentional.

        $config{perlenv}->{$name} = $ENV{$name}
            if ! exists $config{perlenv}->{$name};
    }
    return $config{perlenv}->{$name};
}

# Configuration printer ##############################################

sub print_table_entry
{
    local $now_printing = shift;
    my %target = resolve_config($now_printing);
    my $type = shift;

    # Don't print the templates
    return if $target{template};

    my @sequence = (
        "sys_id",
        "cpp",
        "cppflags",
        "defines",
        "includes",
        "cc",
        "cflags",
        "unistd",
        "ld",
        "lflags",
        "loutflag",
        "ex_libs",
        "bn_ops",
        "apps_aux_src",
        "cpuid_asm_src",
        "uplink_aux_src",
        "bn_asm_src",
        "ec_asm_src",
        "des_asm_src",
        "aes_asm_src",
        "bf_asm_src",
        "md5_asm_src",
        "cast_asm_src",
        "sha1_asm_src",
        "rc4_asm_src",
        "rmd160_asm_src",
        "rc5_asm_src",
        "wp_asm_src",
        "cmll_asm_src",
        "modes_asm_src",
        "padlock_asm_src",
        "chacha_asm_src",
        "poly1035_asm_src",
        "thread_scheme",
        "perlasm_scheme",
        "dso_scheme",
        "shared_target",
        "shared_cflag",
        "shared_defines",
        "shared_ldflag",
        "shared_rcflag",
        "shared_extension",
        "dso_extension",
        "obj_extension",
        "exe_extension",
        "ranlib",
        "ar",
        "arflags",
        "aroutflag",
        "rc",
        "rcflags",
        "rcoutflag",
        "mt",
        "mtflags",
        "mtinflag",
        "mtoutflag",
        "multilib",
        "build_scheme",
        );

    if ($type eq "TABLE") {
        print "\n";
        print "*** $now_printing\n";
        foreach (@sequence) {
            if (ref($target{$_}) eq "ARRAY") {
                printf "\$%-12s = %s\n", $_, join(" ", @{$target{$_}});
            } else {
                printf "\$%-12s = %s\n", $_, $target{$_};
            }
        }
    } elsif ($type eq "HASH") {
        my $largest =
            length((sort { length($a) <=> length($b) } @sequence)[-1]);
        print "    '$now_printing' => {\n";
        foreach (@sequence) {
            if ($target{$_}) {
                if (ref($target{$_}) eq "ARRAY") {
                    print "      '",$_,"'"," " x ($largest - length($_))," => [ ",join(", ", map { "'$_'" } @{$target{$_}})," ],\n";
                } else {
                    print "      '",$_,"'"," " x ($largest - length($_))," => '",$target{$_},"',\n";
                }
            }
        }
        print "    },\n";
    }
}

# Utility routines ###################################################

# On VMS, if the given file is a logical name, File::Spec::Functions
# will consider it an absolute path.  There are cases when we want a
# purely syntactic check without checking the environment.
sub isabsolute {
    my $file = shift;

    # On non-platforms, we just use file_name_is_absolute().
    return file_name_is_absolute($file) unless $^O eq "VMS";

    # If the file spec includes a device or a directory spec,
    # file_name_is_absolute() is perfectly safe.
    return file_name_is_absolute($file) if $file =~ m|[:\[]|;

    # Here, we know the given file spec isn't absolute
    return 0;
}

# Makes a directory absolute and cleans out /../ in paths like foo/../bar
# On some platforms, this uses rel2abs(), while on others, realpath() is used.
# realpath() requires that at least all path components except the last is an
# existing directory.  On VMS, the last component of the directory spec must
# exist.
sub absolutedir {
    my $dir = shift;

    # realpath() is quite buggy on VMS.  It uses LIB$FID_TO_NAME, which
    # will return the volume name for the device, no matter what.  Also,
    # it will return an incorrect directory spec if the argument is a
    # directory that doesn't exist.
    if ($^O eq "VMS") {
        return rel2abs($dir);
    }

    # We use realpath() on Unix, since no other will properly clean out
    # a directory spec.
    use Cwd qw/realpath/;

    return realpath($dir);
}

# Check if all paths are one and the same, using stat.  They must both exist
# We need this for the cases when File::Spec doesn't detect case insensitivity
# (File::Spec::Unix assumes case sensitivity)
sub samedir {
    die "samedir expects two arguments\n" unless scalar @_ == 2;

    my @stat0 = stat($_[0]);    # First argument
    my @stat1 = stat($_[1]);    # Second argument

    die "Couldn't stat $_[0]" unless @stat0;
    die "Couldn't stat $_[1]" unless @stat1;

    # Compare device number
    return 0 unless ($stat0[0] == $stat1[0]);
    # Compare "inode".  The perl manual recommends comparing as
    # string rather than as number.
    return 0 unless ($stat0[1] eq $stat1[1]);

    return 1;                   # All the same
}

sub quotify {
    my %processors = (
        perl    => sub { my $x = shift;
                         $x =~ s/([\\\$\@"])/\\$1/g;
                         return '"'.$x.'"'; },
        maybeshell => sub { my $x = shift;
                            (my $y = $x) =~ s/([\\\"])/\\$1/g;
                            if ($x ne $y || $x =~ m|\s|) {
                                return '"'.$y.'"';
                            } else {
                                return $x;
                            }
                        },
        );
    my $for = shift;
    my $processor =
        defined($processors{$for}) ? $processors{$for} : sub { shift; };

    return map { $processor->($_); } @_;
}

# collect_from_file($filename, $line_concat_cond_re, $line_concat)
# $filename is a file name to read from
# $line_concat_cond_re is a regexp detecting a line continuation ending
# $line_concat is a CODEref that takes care of concatenating two lines
sub collect_from_file {
    my $filename = shift;
    my $line_concat_cond_re = shift;
    my $line_concat = shift;

    open my $fh, $filename || die "unable to read $filename: $!\n";
    return sub {
        my $saved_line = "";
        $_ = "";
        while (<$fh>) {
            s|\R$||;
            if (defined $line_concat) {
                $_ = $line_concat->($saved_line, $_);
                $saved_line = "";
            }
            if (defined $line_concat_cond_re && /$line_concat_cond_re/) {
                $saved_line = $_;
                next;
            }
            return $_;
        }
        die "$filename ending with continuation line\n" if $_;
        close $fh;
        return undef;
    }
}

# collect_from_array($array, $line_concat_cond_re, $line_concat)
# $array is an ARRAYref of lines
# $line_concat_cond_re is a regexp detecting a line continuation ending
# $line_concat is a CODEref that takes care of concatenating two lines
sub collect_from_array {
    my $array = shift;
    my $line_concat_cond_re = shift;
    my $line_concat = shift;
    my @array = (@$array);

    return sub {
        my $saved_line = "";
        $_ = "";
        while (defined($_ = shift @array)) {
            s|\R$||;
            if (defined $line_concat) {
                $_ = $line_concat->($saved_line, $_);
                $saved_line = "";
            }
            if (defined $line_concat_cond_re && /$line_concat_cond_re/) {
                $saved_line = $_;
                next;
            }
            return $_;
        }
        die "input text ending with continuation line\n" if $_;
        return undef;
    }
}

# collect_information($lineiterator, $line_continue, $regexp => $CODEref, ...)
# $lineiterator is a CODEref that delivers one line at a time.
# All following arguments are regex/CODEref pairs, where the regexp detects a
# line and the CODEref does something with the result of the regexp.
sub collect_information {
    my $lineiterator = shift;
    my %collectors = @_;

    while(defined($_ = $lineiterator->())) {
        s|\R$||;
        my $found = 0;
        if ($collectors{"BEFORE"}) {
            $collectors{"BEFORE"}->($_);
        }
        foreach my $re (keys %collectors) {
            if ($re !~ /^OTHERWISE|BEFORE|AFTER$/ && /$re/) {
                $collectors{$re}->($lineiterator);
                $found = 1;
            };
        }
        if ($collectors{"OTHERWISE"}) {
            $collectors{"OTHERWISE"}->($lineiterator, $_)
                unless $found || !defined $collectors{"OTHERWISE"};
        }
        if ($collectors{"AFTER"}) {
            $collectors{"AFTER"}->($_);
        }
    }
}

# tokenize($line)
# $line is a line of text to split up into tokens
# returns a list of tokens
#
# Tokens are divided by spaces.  If the tokens include spaces, they
# have to be quoted with single or double quotes.  Double quotes
# inside a double quoted token must be escaped.  Escaping is done
# with backslash.
# Basically, the same quoting rules apply for " and ' as in any
# Unix shell.
sub tokenize {
    my $line = my $debug_line = shift;
    my @result = ();

    while ($line =~ s|^\s+||, $line ne "") {
        my $token = "";
        while ($line ne "" && $line !~ m|^\s|) {
            if ($line =~ m/^"((?:[^"\\]+|\\.)*)"/) {
                $token .= $1;
                $line = $';
            } elsif ($line =~ m/^'([^']*)'/) {
                $token .= $1;
                $line = $';
            } elsif ($line =~ m/^(\S+)/) {
                $token .= $1;
                $line = $';
            }
        }
        push @result, $token;
    }

    if ($ENV{CONFIGURE_DEBUG_TOKENIZE}) {
        print STDERR "DEBUG[tokenize]: Parsed '$debug_line' into:\n";
        print STDERR "DEBUG[tokenize]: ('", join("', '", @result), "')\n";
    }
    return @result;
}