vanilla build of 7.7p1 release on linux/4.17 fails with gcc8 @ "/usr/bin/ld: unrecognized option '-Wl,-z,retpolineplt'"

[Darren Tucker]

On Thu, Jun 07, 2018 at 06:14:42PM -0700, PGNet Dev wrote:
> On 6/7/18 6:08 PM, Darren Tucker wrote:
> > Well the intent is you should be able to set CC and LD to whatever you
> > want as long as they work.  In this case, the OSSH_CHECK_LDFLAG_LINK
> > test invokes autoconf's AC_LINK_IFELSE with uses CC not LD.  I'm not
> > sure what to do about it yet though.

I don't see a way to get AC_LINK_IFELSE to use $LD rather than $CC,
but I think we can prevent this problem by detecting the unsupported
option earlier.  Please try this diff.  It should also prevent the
warnings in the LD=gcc case.

(Note you will need to run "autoreconf" to rebuild configure after
applying it, then run ./configure.)

diff --git a/aclocal.m4 b/aclocal.m4
index ac6b6684..8b4ba126 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -25,14 +25,14 @@ int main(int argc, char **argv) {
 }
 	]])],
 		[
-if `grep -i "unrecognized option" conftest.err >/dev/null`
+if $ac_cv_path_EGREP -i "unrecognized option|warning.*ignored" conftest.err >/dev/null
 then
 		AC_MSG_RESULT([no])
 		CFLAGS="$saved_CFLAGS"
 else
 		AC_MSG_RESULT([yes])
 		 CFLAGS="$saved_CFLAGS $_define_flag"
-fi],
+fi		],
 		[ AC_MSG_RESULT([no])
 		  CFLAGS="$saved_CFLAGS" ]
 	)
@@ -63,7 +63,7 @@ int main(int argc, char **argv) {
 }
 	]])],
 		[
-if `grep -i "unrecognized option" conftest.err >/dev/null`
+if $ac_cv_path_EGREP -i "unrecognized option|warning.*ignored" conftest.err >/dev/null
 then
 		AC_MSG_RESULT([no])
 		CFLAGS="$saved_CFLAGS"
@@ -100,8 +100,15 @@ int main(int argc, char **argv) {
 	exit(0);
 }
 		]])],
-		[ AC_MSG_RESULT([yes])
-		  LDFLAGS="$saved_LDFLAGS $_define_flag"],
+		[
+if `$ac_cv_path_EGREP -i "unrecognized option|warning.*ignored" conftest.err >/dev/null`
+then
+		AC_MSG_RESULT([no])
+		LDFLAGS="$saved_LDFLAGS"
+else
+		AC_MSG_RESULT([yes])
+		LDFLAGS="$saved_LDFLAGS $_define_flag"
+fi		],
 		[ AC_MSG_RESULT([no])
 		  LDFLAGS="$saved_LDFLAGS" ]
 	)

-- 
Darren Tucker (dtucker at dtucker.net)
GPG key 11EAA6FA / A86E 3E07 5B19 5880 E860  37F4 9357 ECEF 11EA A6FA (new)
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.