diff options
Diffstat (limited to 'm4')
| -rw-r--r-- | m4/attributes.m4 | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/m4/attributes.m4 b/m4/attributes.m4 index 4b0fcdce3d..db5df250f4 100644 --- a/m4/attributes.m4 +++ b/m4/attributes.m4 @@ -35,15 +35,18 @@ dnl well. dnl Check if FLAG in ENV-VAR is supported by compiler and append it dnl to WHERE-TO-APPEND variable. Note that we invert -Wno-* checks to -dnl -W* as gcc cannot test for negated warnings. -dnl CC_CHECK_FLAG_APPEND([WHERE-TO-APPEND], [ENV-VAR], [FLAG]) +dnl -W* as gcc cannot test for negated warnings. If a C snippet is passed, +dnl use it, otherwise use a simple main() definition that just returns 0. +dnl CC_CHECK_FLAG_APPEND([WHERE-TO-APPEND], [ENV-VAR], [FLAG], [C-SNIPPET]) AC_DEFUN([CC_CHECK_FLAG_APPEND], [ AC_CACHE_CHECK([if $CC supports flag $3 in envvar $2], AS_TR_SH([cc_cv_$2_$3]), [eval "AS_TR_SH([cc_save_$2])='${$2}'" eval "AS_TR_SH([$2])='-Werror `echo "$3" | sed 's/^-Wno-/-W/'`'" - AC_LINK_IFELSE([AC_LANG_SOURCE([int main(void) { return 0; } ])], + AC_LINK_IFELSE([AC_LANG_SOURCE(ifelse([$4], [], + [int main(void) { return 0; } ], + [$4]))], [eval "AS_TR_SH([cc_cv_$2_$3])='yes'"], [eval "AS_TR_SH([cc_cv_$2_$3])='no'"]) eval "AS_TR_SH([$2])='$cc_save_$2'"]) @@ -52,10 +55,10 @@ AC_DEFUN([CC_CHECK_FLAG_APPEND], [ [eval "$1='${$1} $3'"]) ]) -dnl CC_CHECK_FLAGS_APPEND([WHERE-TO-APPEND], [ENV-VAR], [FLAG1 FLAG2]) +dnl CC_CHECK_FLAGS_APPEND([WHERE-TO-APPEND], [ENV-VAR], [FLAG1 FLAG2], [C-SNIPPET]) AC_DEFUN([CC_CHECK_FLAGS_APPEND], [ for flag in [$3]; do - CC_CHECK_FLAG_APPEND([$1], [$2], $flag) + CC_CHECK_FLAG_APPEND([$1], [$2], $flag, [$4]) done ]) |