1 files changed, 62 insertions, 0 deletions
diff --git a/config/clang-plugin.m4 b/config/clang-plugin.m4
new file mode 100644
index 0000000..ce7307c
--- /dev/null
+++ b/config/clang-plugin.m4
@@ -0,0 +1,62 @@
+# clang-plugin.m4 -*- Autoconf -*-
+# Check clang plugin file.
+
+dnl Copyright (C) 2025 Free Software Foundation, Inc.
+dnl This file is free software, distributed under the terms of the GNU
+dnl General Public License.  As a special exception to the GNU General
+dnl Public License, this file may be distributed as part of a program
+dnl that contains a configuration script generated by Autoconf, under
+dnl the same distribution terms as the rest of that program.
+
+dnl
+dnl
+dnl CLANG_PLUGIN_FILE
+dnl    (SHELL-CODE_HANDLER)
+dnl
+AC_DEFUN([CLANG_PLUGIN_FILE],[dnl
+  AC_CACHE_CHECK([for clang], clang_cv_is_clang, [
+    AC_EGREP_CPP(yes, [
+#ifdef __clang__
+  yes
+#endif
+    ], clang_cv_is_clang=yes, clang_cv_is_clang=no)])
+  plugin_file=
+  if test $clang_cv_is_clang = yes; then
+    AC_MSG_CHECKING([for clang plugin file])
+    plugin_names="LLVMgold.so"
+    for plugin in $plugin_names; do
+      plugin_file=`${CC} ${CFLAGS} --print-file-name $plugin`
+      if test x$plugin_file = x$plugin; then
+	AC_CHECK_TOOL(LLVM_CONFIG, llvm-config)
+	if test "$?" != 0; then
+	  AC_MSG_ERROR([Required tool 'llvm-config' not found on PATH.])
+	fi
+	clang_lib_dir=`$LLVM_CONFIG --libdir`
+	if test -f $clang_lib_dir/$plugin; then
+	  plugin_file=$clang_lib_dir/$plugin
+	fi
+	if test x$plugin_file != x$plugin; then
+	  break;
+	fi
+      fi
+    done
+    if test -z $plugin_file; then
+      AC_MSG_ERROR([Couldn't find clang plugin file for $CC.])
+    fi
+    dnl Check if ${AR} $plugin_option rc works.
+    AC_CHECK_TOOL(AR, ar)
+    if test "${AR}" = "" ; then
+      AC_MSG_ERROR([Required archive tool 'ar' not found on PATH.])
+    fi
+    plugin_option="--plugin $plugin_file"
+    touch conftest.c
+    ${AR} $plugin_option rc conftest.a conftest.c
+    if test "$?" != 0; then
+      AC_MSG_WARN([Failed: $AR $plugin_option rc])
+      plugin_file=
+    fi
+    rm -f conftest.*
+    AC_MSG_RESULT($plugin_file)
+  fi
+  $1="$plugin_file"
+])