+
+if test -f config_h.SH -a ! -f config.h; then
+ . ./config_h.SH
+ CONFIG_H=already-done
+fi
+
+warn=''
+
+# Add -Wall for the core modules iff gcc and not already -Wall
+case "$gccversion" in
+'') ;;
+Intel*) ;; # The Intel C++ plays gcc on TV but is not really it.
+*) case "$ccflags" in
+ *-Wall*) ;;
+ *) warn="$warn -Wall" ;;
+ esac
+ ;;
+esac
+
+# Create a test source file for testing what options can be fed to
+# gcc in this system; include a selection of most common and commonly
+# hairy include files.
+
+cat >_cflags.c <<__EOT__
+#include "EXTERN.h"
+#include "perl.h"
+/* The stdio.h, errno.h, and setjmp.h should be there in any ANSI C89. */
+#include <stdio.h>
+#include <errno.h>
+#include <setjmp.h>
+/* Just in case the inclusion of perl.h did not
+ * pull in enough system headers, let's try again. */
+#ifdef I_STDLIB
+#include <stdlib.h>
+#endif
+#ifdef I_STDDEF
+#include <stddef.h>
+#endif
+#ifdef I_STDARG
+#include <stdarg.h>
+#endif
+#ifdef I_LIMITS
+#include <limits.h>
+#endif
+#ifdef I_DIRENT
+#include <dirent.h>
+#endif
+#ifdef I_UNISTD
+#include <unistd.h>
+#endif
+#ifdef I_SYS_TYPES
+#include <sys/types.h>
+#endif
+#ifdef I_SYS_PARAM
+#include <sys/param.h>
+#endif
+#ifdef I_SYS_RESOURCE
+#include <sys/resource.h>
+#endif
+#ifdef I_SYS_SELECT
+#include <sys/select.h>
+#endif
+#if defined(HAS_SOCKET) && !defined(VMS) && !defined(WIN32) /* See perl.h. */
+#include <sys/socket.h>
+#endif
+#ifdef I_SYS_STAT
+#include <sys/stat.h>
+#endif
+#ifdef I_SYS_TIME
+#include <sys/time.h>
+#endif
+#ifdef I_SYS_TIMES
+#include <sys/times.h>
+#endif
+#ifdef I_SYS_WAIT
+#include <sys/wait.h>
+#endif
+/* The gcc -ansi can cause a lot of noise in Solaris because of:
+ /usr/include/sys/resource.h:148: warning: 'struct rlimit64' declared inside parameter list
+ */
+int main(int argc, char *argv[]) {
+
+/* Add here test code found to be problematic in some gcc platform. */
+
+/* Off_t/off_t is a struct in Solaris with largefiles, and with gcc -ansi
+ * that struct cannot be compared in some gcc releases with a flat
+ * integer, such as a STRLEN. */
+
+ IV iv;
+ Off_t t0a = 2;
+ STRLEN t0b = 3;
+ int t0c = t0a == t0b;
+
+/* In FreeBSD 6.2 (and probably other releases too), with -Duse64bitint,
+ perl will use atoll(3). However, that declaration is hidden in <stdlib.h>
+ if we force the compiler to use -std=c89 mode.
+*/
+ iv = Atol("42");
+
+ return (!t0c && (iv == 42)) ? 0 : -1; /* Try to avoid 'unused' warnings. */
+}
+__EOT__
+
+stdflags=''
+
+# Further gcc warning options. Build up a list of options that work.
+# Note that some problems may only show up with combinations of options,
+# e.g. a warning might show up only with -Wall -ansi, not with either
+# one individually.
+# TODO: Ponder whether to migrate this back to Configure so hints files can
+# tweak it. Also, be paranoid about whether results we've deduced in Configure
+# (especially about things like long long, which are not in C89) will still be
+# valid if we now add flags like -std=c89.
+
+case "$gccversion" in
+'') ;;
+[12]*) ;; # gcc versions 1 (gasp!) and 2 are not good for this.
+Intel*) ;; # # Is that you, Intel C++?
+*) for opt in -ansi -std=c89 -W -Wextra -Wdeclaration-after-statement \
+ -Wendif-labels -Wc++-compat -Wwrite-strings
+ do
+ case " $ccflags " in
+ *" $opt "*) ;; # Skip if already there.
+ *) rm -f _cflags$_exe
+ case "`$cc $cflags $warn $stdflags $opt _cflags.c -o _cflags$_exe 2>&1`" in
+ *"unrecognized"*) ;;
+ *"implicit declaration"*) ;; # Was something useful hidden?
+ *"Invalid"*) ;;
+ *"is valid for C"*) ;;
+ *) if test -x _cflags$_exe
+ then
+ case "$opt" in
+ -std*) stdflags="$stdflags $opt" ;;
+ *) warn="$warn $opt" ;;
+ esac
+ fi
+ ;;
+ esac
+ ;;
+ esac
+ done
+ ;;
+esac
+rm -f _cflags.c _cflags$_exe
+
+case "$gccversion" in
+'') ;;
+*)
+ if [ "$gccansipedantic" = "" ]; then
+ # If we have -Duse64bitint (or equivalent) in effect and the quadtype
+ # has become 'long long', gcc -pedantic becomes unbearable (moreso
+ # when combined with -Wall) because long long and LL and %lld|%Ld
+ # become warn-worthy. So let's drop the -pedantic in that case.
+ case "$quadtype:$sPRId64" in
+ "long long"*|*lld*|*Ld*)
+ ccflags="`echo $ccflags|sed 's/-pedantic/ /'`"
+ warn="`echo $warn|sed 's/-pedantic/ /'`"
+ ;;
+ esac
+ # Similarly, since 'long long' isn't part of C89, FreeBSD 6.2 headers
+ # don't declare atoll() under -std=c89, but we need it. In general,
+ # insisting on -std=c89 is inconsistent with insisting on using
+ # 'long long'. So drop -std=c89 and -ansi as well if we're using
+ # 'long long' as our main integral type.
+ case "$ivtype" in
+ "long long")
+ ccflags=`echo $ccflags|sed -e 's/-pedantic/ /' -e 's/-std=c89/ /' -e 's/-ansi/ /'`
+ warn=`echo $warn|sed -e 's/-pedantic/ /' -e 's/-ansi/ /'`
+ stdflags=`echo $stdflags|sed -e 's/-std=c89/ /'`
+ ;;
+ esac
+ fi
+ # Using certain features (like the gcc statement expressions)
+ # requires knowing whether -pedantic has been specified.
+ case "$warn$ccflags" in
+ *-pedantic*) warn="$warn -DPERL_GCC_PEDANTIC" ;;
+ esac
+ ;;
+esac
+
+# Code to set any extra flags here.
+extra=''
+