From: Arsen Arsenović <arsen@aarsen.me>
Date: Wed, 8 Mar 2023 16:01:24 +0000 (+0100)
Subject: libstdc++: Add a test for <version> FTM redefinitions
X-Git-Tag: basepoints/gcc-14~191
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6f0d67b912900009bff5018bd58e17ea1db1de69;p=thirdparty%2Fgcc.git

libstdc++: Add a test for <version> FTM redefinitions

This test detects redefinitions by compiling stdc++.h and <version>, by
disabling the system_header pragma on the latter, to allow warnings in
it.  Thanks Patrick Palka for the suggestion.

libstdc++-v3/ChangeLog:

	* testsuite/17_intro/versionconflict.cc: New test.
	* include/std/version: Allow disabling the system_header pragma
	via _GLIBCXX_TESTING_SYSHDR.
---

diff --git a/libstdc++-v3/include/std/version b/libstdc++-v3/include/std/version
index cdd24248c57c..1069bc6c9f6f 100644
--- a/libstdc++-v3/include/std/version
+++ b/libstdc++-v3/include/std/version
@@ -30,7 +30,10 @@
 #ifndef _GLIBCXX_VERSION_INCLUDED
 #define _GLIBCXX_VERSION_INCLUDED
 
-#pragma GCC system_header
+// To facilitate testsuite/17_intro/versionconflict.cc
+#ifndef _GLIBCXX_TESTING_SYSHDR
+# pragma GCC system_header
+#endif
 
 #include <bits/c++config.h>
 
diff --git a/libstdc++-v3/testsuite/17_intro/versionconflict.cc b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
new file mode 100644
index 000000000000..6c212980ab06
--- /dev/null
+++ b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
@@ -0,0 +1,7 @@
+// { dg-do preprocess }
+// { dg-additional-options "-Werror" }
+
+// Test for redefinitions of FTMs using bits/stdc++.h.
+#define _GLIBCXX_TESTING_SYSHDR
+#include <bits/stdc++.h>
+#include <version>