[gcc(refs/users/marxin/heads/PR106156-fix-riscv64-lto-plugin-v2)] lto-plugin: use -pthread only for detected targets

[Martin Liska <marxin@gcc.gnu.org>]

https://gcc.gnu.org/g:d3a5ce1c0ead2bc64e8428ac3fc7b4c1ee69e8aa

commit d3a5ce1c0ead2bc64e8428ac3fc7b4c1ee69e8aa
Author: Martin Liska <mliska@suse.cz>
Date:   Wed Jul 13 09:39:34 2022 +0200

    lto-plugin: use -pthread only for detected targets
    
    Use -pthread only if we are going to use pthread functionality.
    
    lto-plugin/ChangeLog:
    
            * configure: Regenerate.
            * configure.ac: Use -pthread only why use_locking == true.
            * Makefile.in: Rely on ac_lto_plugin_ldflags.

Diff:
---
 lto-plugin/Makefile.in  | 2 +-
 lto-plugin/configure    | 6 ++++--
 lto-plugin/configure.ac | 2 ++
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/lto-plugin/Makefile.in b/lto-plugin/Makefile.in
index 9453bc7d607..6b161c01683 100644
--- a/lto-plugin/Makefile.in
+++ b/lto-plugin/Makefile.in
@@ -345,7 +345,7 @@ libexecsubdir := $(libexecdir)/gcc/$(real_target_noncanonical)/$(gcc_version)$(a
 AM_CPPFLAGS = -I$(top_srcdir)/../include $(DEFS)
 AM_CFLAGS = @ac_lto_plugin_warn_cflags@ $(CET_HOST_FLAGS) -DBASE_VERSION='"$(gcc_version)"'
 # The plug-in depends on pthreads.
-AM_LDFLAGS = -pthread @ac_lto_plugin_ldflags@
+AM_LDFLAGS = @ac_lto_plugin_ldflags@
 AM_LIBTOOLFLAGS = --tag=disable-static
 libexecsub_LTLIBRARIES = liblto_plugin.la
 in_gcc_libs = $(foreach lib, $(libexecsub_LTLIBRARIES), $(gcc_build_dir)/$(lib))
diff --git a/lto-plugin/configure b/lto-plugin/configure
index 870e49b2e62..0967ba1c798 100755
--- a/lto-plugin/configure
+++ b/lto-plugin/configure
@@ -6023,6 +6023,8 @@ case $target in
 esac
 
 if test x$use_locking = xyes; then
+  LDFLAGS="$LDFLAGS -pthread"
+
   ac_fn_c_check_header_mongrel "$LINENO" "pthread.h" "ac_cv_header_pthread_h" "$ac_includes_default"
 if test "x$ac_cv_header_pthread_h" = xyes; then :
 
@@ -12104,7 +12106,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12107 "configure"
+#line 12109 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12210,7 +12212,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12213 "configure"
+#line 12215 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/lto-plugin/configure.ac b/lto-plugin/configure.ac
index 18eb4f60b0a..a350aa56a8b 100644
--- a/lto-plugin/configure.ac
+++ b/lto-plugin/configure.ac
@@ -100,6 +100,8 @@ case $target in
 esac
 
 if test x$use_locking = xyes; then
+  LDFLAGS="$LDFLAGS -pthread"
+
   AC_CHECK_HEADER(pthread.h,
     [AC_DEFINE(HAVE_PTHREAD_LOCKING, 1, [Define if the system provides pthread locking mechanism.])])
 fi