PR c++/19555

	* cp-tree.h (DECL_USE_TEMPLATE): Expand documentation.
	* decl.c (duplicate_decls): Do not discard
	DECL_IMPLICIT_INSTANTIATION when merging declarations.
	(start_decl): Do not SET_DECL_TEMPLATE_SPECIALIZATION for
	variables that do not have DECL_USE_TEMPLATE.

	PR c++/19555
	* g++.dg/template/static10.C: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@94469 138bc75d-0d04-0410-961f-82ee72b054a4

5 files changed, 51 insertions, 3 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 0b1f7d1a3de..e205886c863 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,12 @@
 2005-01-30  Mark Mitchell  <mark@codesourcery.com>
 
+	PR c++/19555
+	* cp-tree.h (DECL_USE_TEMPLATE): Expand documentation.
+	* decl.c (duplicate_decls): Do not discard
+	DECL_IMPLICIT_INSTANTIATION when merging declarations.
+	(start_decl): Do not SET_DECL_TEMPLATE_SPECIALIZATION for
+	variables that do not have DECL_USE_TEMPLATE.
+
 	PR c++/19395
 	* decl.c (grokdeclarator): Refactor code so that qualified names
 	are never allowed as the declarator in a typedef.
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index ced845b8428..cb0c25b3694 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -2779,7 +2779,10 @@ struct lang_decl GTY(())
      0=normal declaration, e.g. int min (int, int);
      1=implicit template instantiation
      2=explicit template specialization, e.g. int min<int> (int, int);
-     3=explicit template instantiation, e.g. template int min<int> (int, int);  */
+     3=explicit template instantiation, e.g. template int min<int> (int, int);
+
+   If DECL_USE_TEMPLATE is non-zero, then DECL_TEMPLATE_INFO will also
+   be non-NULL.  */
 #define DECL_USE_TEMPLATE(NODE) (DECL_LANG_SPECIFIC (NODE)->decl_flags.use_template)
 
 #define DECL_TEMPLATE_INSTANTIATION(NODE) (DECL_USE_TEMPLATE (NODE) & 1)
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index e2408e36b82..e72b183c6b6 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -1669,6 +1669,13 @@ duplicate_decls (tree newdecl, tree olddecl)
       DECL_COMDAT (newdecl) |= DECL_COMDAT (olddecl);
       DECL_TEMPLATE_INSTANTIATED (newdecl)
 	|= DECL_TEMPLATE_INSTANTIATED (olddecl);
+      /* If the OLDDECL is an implicit instantiation, then the NEWDECL
+	 must be too.  But, it may not yet be marked as such if the
+	 caller has created NEWDECL, but has not yet figured out that
+	 it is a redeclaration.  */
+      if (DECL_IMPLICIT_INSTANTIATION (olddecl)
+	  && !DECL_USE_TEMPLATE (newdecl))
+	SET_DECL_IMPLICIT_INSTANTIATION (newdecl);
       /* Don't really know how much of the language-specific
 	 values we should copy from old to new.  */
       DECL_IN_AGGR_P (newdecl) = DECL_IN_AGGR_P (olddecl);
@@ -3695,10 +3702,15 @@ start_decl (const cp_declarator *declarator,
 
       /* cp_finish_decl sets DECL_EXTERNAL if DECL_IN_AGGR_P is set.  */
       DECL_IN_AGGR_P (decl) = 0;
-      if ((DECL_LANG_SPECIFIC (decl) && DECL_USE_TEMPLATE (decl))
+      if (DECL_LANG_SPECIFIC (decl) && DECL_USE_TEMPLATE (decl)
 	  || CLASSTYPE_TEMPLATE_INSTANTIATION (context))
 	{
-	  SET_DECL_TEMPLATE_SPECIALIZATION (decl);
+	  /* Do not mark DECL as an explicit specialization if it was
+	     not already marked as an instantiation; a declaration
+	     should never be marked as a specialization unless we know
+	     what template is being specialized.  */ 
+	  if (DECL_LANG_SPECIFIC (decl) && DECL_USE_TEMPLATE (decl))
+	    SET_DECL_TEMPLATE_SPECIALIZATION (decl);
 	  /* [temp.expl.spec] An explicit specialization of a static data
 	     member of a template is a definition if the declaration
 	     includes an initializer; otherwise, it is a declaration.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 0d7f5306e9d..30a3bca86f1 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2005-01-30  Mark Mitchell  <mark@codesourcery.com>
 
+	PR c++/19555
+	* g++.dg/template/static10.C: New test.
+
 	PR c++/19395
 	* g++.dg/parse/error24.C: New test. 
 
diff --git a/gcc/testsuite/g++.dg/template/static10.C b/gcc/testsuite/g++.dg/template/static10.C
new file mode 100644
index 00000000000..ab857bd814e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/static10.C
@@ -0,0 +1,23 @@
+// PR c++/19555
+
+namespace __gnu_debug_def { }
+namespace std
+{
+  using namespace __gnu_debug_def;
+  template<typename _Tp> class allocator {};
+}
+namespace __gnu_debug_def
+{
+  template<typename _Tp,
+    typename _Allocator = std::allocator<_Tp> >
+    class vector
+    {
+      void
+      swap(vector<_Tp,_Allocator>& __x);
+    };
+}
+namespace std
+{
+  template<> void
+  vector<int, allocator<int> >::swap(vector<int, allocator<int> >&) { } // { dg-error "" }
+}