From: Sebastian Huber <sebastian.huber@embedded-brains.de>
Date: Wed, 14 Jul 2021 07:40:11 +0000 (+0200)
Subject: gcov: Fix use of profile info section
X-Git-Tag: basepoints/gcc-13~5878
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f8884b9c51faea329196bf5914bcd2d700622c38;p=thirdparty%2Fgcc.git

gcov: Fix use of profile info section

If the -fprofile-info-section is used, then the gcov information is registered
in a linker set.  This is done by build_gcov_info_var_registration().  The
compiler generated object placed in the section was not marked as referenced,
so once optimization was enabled, this object was optimized away.  Mark it as
referenced.

gcc/
	* coverage.c (build_gcov_info_var_registration): Mark the object placed
	in the linker set as referenced so that it does not get optimized away.
---

diff --git a/gcc/coverage.c b/gcc/coverage.c
index dfc8108d5d83..ac9a9fdad228 100644
--- a/gcc/coverage.c
+++ b/gcc/coverage.c
@@ -50,6 +50,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "auto-profile.h"
 #include "profile.h"
 #include "diagnostic.h"
+#include "varasm.h"
 
 #include "gcov-io.c"
 
@@ -1121,6 +1122,7 @@ build_gcov_info_var_registration (tree gcov_info_type)
   DECL_NAME (var) = get_identifier (name_buf);
   get_section (profile_info_section, SECTION_UNNAMED, NULL);
   set_decl_section_name (var, profile_info_section);
+  mark_decl_referenced (var);
   DECL_INITIAL (var) = build_fold_addr_expr (gcov_info_var);
   varpool_node::finalize_decl (var);
 }