From: Jan André Reuter <j.reuter@fz-juelich.de>
Date: Wed, 3 Dec 2025 11:59:43 +0000 (+0100)
Subject: Ignore target feature flags in _AC_FC_LIBRARY_LDFLAGS (#111353)
X-Git-Tag: v2.72.90~15
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=16de3c26a54dced1d1ef548de7bd4aa45ea2a773;p=thirdparty%2Fautoconf.git

Ignore target feature flags in _AC_FC_LIBRARY_LDFLAGS (#111353)

Ignore target specific feature flags passed via '-target-feature'.
When encountered, ignore the flag passed after. These flags might
contain a '-l', e.g. '-target-feature -lwp', causing non-existent
libraries to be picked up, failing later checks, or the build of
the application.

This can e.g. be encountered when '-march=native' is passed to
configure during a build with LLVM on Zen 4 machines.

Reported by, and patch written by, Jan André Reuter <j.reuter@fz-juelich.de>.

* lib/autoconf/fortran.m4 (_AC_FC_LIBRARY_LDFLAGS): Skip arguments
  immediately following ‘-target-feature’.
---

diff --git a/lib/autoconf/fortran.m4 b/lib/autoconf/fortran.m4
index 87e00cc67..5d34f1182 100644
--- a/lib/autoconf/fortran.m4
+++ b/lib/autoconf/fortran.m4
@@ -676,6 +676,12 @@ while test $[@%:@] != 1; do
 	    ;;
 	  esac
 	  ;;
+	-target-feature)
+	  # for target specific feature flags, ignore the next argument,
+	  # which may include a feature starting with -l
+	  # (e.g -target-feature -lwp)
+	  shift;
+	  ;;
 	-[[LRuYz]])
 	  # These flags, when seen by themselves, take an argument.
 	  # We remove the space between option and argument and re-iterate