From fc97053254977c2709b8eca3caed6558e2ade7e2 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Fri, 13 Jan 2012 12:50:58 -0500
Subject: [PATCH] re PR c++/51813 (-fvisibility=hidden causes std::codecvt
 members to be undefined)

	PR c++/51813
	* decl2.c (constrain_visibility): Clear DECL_VISIBILITY_SPECIFIED
	when reducing the visibility.

From-SVN: r183156
---
 gcc/cp/ChangeLog                                |  4 ++++
 gcc/cp/decl2.c                                  |  2 ++
 gcc/testsuite/ChangeLog                         |  3 +++
 gcc/testsuite/g++.dg/ext/visibility/template9.C | 14 ++++++++++++++
 4 files changed, 23 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/ext/visibility/template9.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 58210f12e64..19d4eccc45d 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 2012-01-13  Jason Merrill  <jason@redhat.com>
 
+	PR c++/51813
+	* decl2.c (constrain_visibility): Clear DECL_VISIBILITY_SPECIFIED
+	when reducing the visibility.
+
 	PR c++/51620
 	* class.c (build_vtbl_initializer): Use __cxa_deleted_virtual.
 
diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c
index 05f4b42ac73..0cde6c66149 100644
--- a/gcc/cp/decl2.c
+++ b/gcc/cp/decl2.c
@@ -1984,6 +1984,8 @@ constrain_visibility (tree decl, int visibility, bool tmpl)
 	   && (tmpl || !DECL_VISIBILITY_SPECIFIED (decl)))
     {
       DECL_VISIBILITY (decl) = (enum symbol_visibility) visibility;
+      /* This visibility was not specified.  */
+      DECL_VISIBILITY_SPECIFIED (decl) = false;
     }
 }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 2778556b8e3..12d5830a0a2 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2012-01-13  Jason Merrill  <jason@redhat.com>
 
+	PR c++/51813
+	* g++.dg/ext/visibility/template9.C: New.
+
 	PR c++/51620
 	* g++.dg/cpp0x/defaulted34.C: New.
 	* g++.dg/template/virtual3.C: New.
diff --git a/gcc/testsuite/g++.dg/ext/visibility/template9.C b/gcc/testsuite/g++.dg/ext/visibility/template9.C
new file mode 100644
index 00000000000..d1608467269
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/visibility/template9.C
@@ -0,0 +1,14 @@
+// PR c++/51813
+// { dg-options -fvisibility=hidden }
+// { dg-final { scan-assembler-not "hidden\\s+_ZN1N1fI1AEEvT" } }
+
+struct A { };
+namespace N __attribute((visibility("default"))) {
+  template <class T> void f(T) { }
+  extern template void f(A);
+}
+
+int main()
+{
+  N::f(A());
+}