Adds two new default GCC options.

Adds two new default GCC options related to optimizations
(-fno-strict-aliasing and -fno-strict-overflow). This
should fix some hyperaggressive GCC optimizations.

Also updates autoconf option detection.
This commit is contained in:
Ondrej Zajicek 2013-04-17 15:09:50 +02:00
parent 8df02847e8
commit efd6d12b97
2 changed files with 24 additions and 18 deletions

30
aclocal.m4 vendored
View file

@ -133,19 +133,23 @@ if test "$bird_cv_struct_ip_mreqn" = yes ; then
fi
])
AC_DEFUN(BIRD_CHECK_GCC_OPTIONS,
[AC_CACHE_VAL(bird_cv_c_option_no_pointer_sign, [
cat >conftest.c <<EOF
int main(void)
{ return 0; }
EOF
if $CC -Wall -Wno-pointer-sign conftest.c >&AS_MESSAGE_LOG_FD 2>&1 ; then
bird_cv_c_option_no_pointer_sign=yes
else
bird_cv_c_option_no_pointer_sign=no
fi
rm -rf conftest* a.out
])])
AC_DEFUN(BIRD_CHECK_GCC_OPTION,
[
bird_tmp_cflags="$CFLAGS"
CFLAGS="$3 $2"
AC_CACHE_CHECK([whether CC supports $2], $1,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([])], [$1=yes], [$1=no])])
CFLAGS="$bird_tmp_cflags"
])
AC_DEFUN(BIRD_ADD_GCC_OPTION,
[
if test "$$1" = yes ; then
CFLAGS="$CFLAGS $2"
fi
])
# BIRD_CHECK_PROG_FLAVOR_GNU(PROGRAM-PATH, IF-SUCCESS, [IF-FAILURE])
# copied autoconf internal _AC_PATH_PROG_FLAVOR_GNU

View file

@ -87,15 +87,17 @@ if test -z "$GCC" ; then
AC_MSG_ERROR([This program requires the GNU C Compiler.])
fi
AC_MSG_CHECKING([what CFLAGS should we use])
if test "$bird_cflags_default" = yes ; then
BIRD_CHECK_GCC_OPTIONS
BIRD_CHECK_GCC_OPTION(bird_cv_c_option_wno_pointer_sign, -Wno-pointer-sign, -Wall)
BIRD_CHECK_GCC_OPTION(bird_cv_c_option_fno_strict_aliasing, -fno-strict-aliasing)
BIRD_CHECK_GCC_OPTION(bird_cv_c_option_fno_strict_overflow, -fno-strict-overflow)
CFLAGS="$CFLAGS -Wall -Wstrict-prototypes -Wno-parentheses"
if test "$bird_cv_c_option_no_pointer_sign" = yes ; then
CFLAGS="$CFLAGS -Wno-pointer-sign"
fi
BIRD_ADD_GCC_OPTION(bird_cv_c_option_wno_pointer_sign, -Wno-pointer-sign)
BIRD_ADD_GCC_OPTION(bird_cv_c_option_fno_strict_aliasing, -fno-strict-aliasing)
BIRD_ADD_GCC_OPTION(bird_cv_c_option_fno_strict_overflow, -fno-strict-overflow)
fi
AC_MSG_CHECKING([CFLAGS])
AC_MSG_RESULT($CFLAGS)