--- a/CPP/7zip/7zip_gcc.mak
+++ b/CPP/7zip/7zip_gcc.mak
@@ -18,13 +18,13 @@ PROGPATH_STATIC = $(O)/$(PROG)s
 
 
 ifneq ($(CC), xlc)
-CFLAGS_WARN_WALL = -Wall -Werror -Wextra
+CFLAGS_WARN_WALL = -Wall -Wextra
 endif
 
 # for object file
 CFLAGS_BASE_LIST = -c
 # CFLAGS_BASE_LIST = -S
-CFLAGS_BASE = -O2 $(CFLAGS_BASE_LIST) $(CFLAGS_WARN_WALL) $(CFLAGS_WARN) \
+CFLAGS_BASE = $(CFLAGS_BASE_LIST) $(CFLAGS_WARN_WALL) $(CFLAGS_WARN) -D_GNU_SOURCE \
  -DNDEBUG -D_REENTRANT -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE \
  -fPIC
 
@@ -192,7 +192,7 @@ all: $(O) $(PROGPATH) $(STATIC_TARGET)
 $(O):
 	$(MY_MKDIR) $(O)
 
-LFLAGS_ALL = -s $(MY_ARCH_2) $(LDFLAGS) $(LD_arch) $(OBJS) $(MY_LIBS) $(LIB2)
+LFLAGS_ALL = $(MY_ARCH_2) $(LDFLAGS) $(LD_arch) $(OBJS) $(MY_LIBS) $(LIB2)
 $(PROGPATH): $(OBJS)
 	$(CXX) -o $(PROGPATH) $(LFLAGS_ALL)
 
