summaryrefslogtreecommitdiffstats
path: root/configure.in
diff options
context:
space:
mode:
Diffstat (limited to 'configure.in')
-rw-r--r--configure.in16
1 files changed, 16 insertions, 0 deletions
diff --git a/configure.in b/configure.in
index 8ab79b5..210eab3 100644
--- a/configure.in
+++ b/configure.in
@@ -641,6 +641,22 @@ AC_SUBST(BASECFLAGS)
# tweak BASECFLAGS based on compiler and platform
case $GCC in
yes)
+ # Python violates C99 rules, by casting between incompatible
+ # pointer types. GCC may generate bad code as a result of that,
+ # so use -fno-strict-aliasing if supported.
+ AC_MSG_CHECKING(whether $CC accepts -fno-strict-aliasing)
+ ac_save_cc="$CC"
+ CC="$CC -fno-strict-aliasing"
+ AC_TRY_RUN([int main() { return 0; }],
+ ac_cv_no_strict_aliasing_ok=yes,
+ ac_cv_no_strict_aliasing_ok=no,
+ ac_cv_no_strict_aliasing_ok=no)
+ CC="$ac_save_cc"
+ AC_MSG_RESULT($ac_cv_no_strict_aliasing_ok)
+ if test $ac_cv_no_strict_aliasing_ok = yes
+ then
+ BASECFLAGS="$BASECFLAGS -fno-strict-aliasing"
+ fi
case $ac_sys_system in
SCO_SV*)
BASECFLAGS="$BASECFLAGS -m486 -DSCO5"