dc: fix '?'

function                                             old     new   delta
zdc_parse_expr                                       470     479      +9
zxc_vm_process                                       839     814     -25
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 9/-25)             Total: -16 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

miscutils/bc.c

@@ -5054,6 +5054,9 @@ static BC_STATUS zdc_parse_expr(void)
 	BcParse *p = &G.prs;
 	int i;
 
+	if (p->lex == XC_LEX_NLINE)
+		RETURN_STATUS(zxc_lex_next());
+
 	i = (int)p->lex - (int)XC_LEX_OP_POWER;
 	if (i >= 0) {
 		BcInst inst = dc_LEX_to_INST[i];
@@ -6766,14 +6769,6 @@ static BC_STATUS zxc_vm_process(const char *text)
 #endif
 		} else {
 #if ENABLE_DC
-			// Most of dc parsing assumes all whitespace,
-			// including '\n', is eaten.
-			while (G.prs.lex == XC_LEX_NLINE) {
-				s = zxc_lex_next();
-				if (s) goto err;
-				if (G.prs.lex == XC_LEX_EOF)
-					goto done;
-			}
 			s = zdc_parse_expr();
 #endif
 		}
@@ -6836,7 +6831,7 @@ static BC_STATUS zxc_vm_process(const char *text)
 		bc_vec_pop_all(&f->code);
 		ip->inst_idx = 0;
 	}
- IF_DC(done:)
+
 	dbg_lex_done("%s:%d done", __func__, __LINE__);
 	RETURN_STATUS(s);
 }

testsuite/dc.tests

@@ -41,6 +41,11 @@ testing "dc complex without spaces (multiple args)" \
 	"16\n" \
 	"" ""
 
+testing "dc read" \
+	"dc -finput" \
+	"2\n9\n1\n" \
+	"1?2\nf" "9\n"
+
 optional FEATURE_DC_BIG
 # All tests below depend on FEATURE_DC_BIG