[C++ Patch] PR 56722

[Paolo Carlini]

Hi,

avoid a Seg fault on invalid by preliminarily checking 
DECL_LANG_SPECIFIC. The resulting error message is very similar to clang's.

Tested x86_64-linux. Ok mainline and branch?

Thanks,
Paolo.

////////////////////////
/cp
2013-03-25  Paolo Carlini  <paolo.carl...@oracle.com>

        PR c++/56722
        * decl.c (cp_finish_decl): Check DECL_LANG_SPECIFIC before
        DECL_TEMPLATE_INSTANTIATION.

/testsuite
2013-03-25  Paolo Carlini  <paolo.carl...@oracle.com>

        PR c++/56722
        * g++.dg/cpp0x/range-for23.C: New.
Index: cp/decl.c
===================================================================
--- cp/decl.c   (revision 197053)
+++ cp/decl.c   (working copy)
@@ -6111,7 +6111,8 @@ cp_finish_decl (tree decl, tree init, bool init_co
       tree d_init;
       if (init == NULL_TREE)
        {
-         if (DECL_TEMPLATE_INSTANTIATION (decl)
+         if (DECL_LANG_SPECIFIC (decl)
+             && DECL_TEMPLATE_INSTANTIATION (decl)
              && !DECL_TEMPLATE_INSTANTIATED (decl))
            {
              /* init is null because we're deferring instantiating the
Index: testsuite/g++.dg/cpp0x/range-for23.C
===================================================================
--- testsuite/g++.dg/cpp0x/range-for23.C        (revision 0)
+++ testsuite/g++.dg/cpp0x/range-for23.C        (working copy)
@@ -0,0 +1,8 @@
+// PR c++/56722
+// { dg-do compile { target c++11 } }
+
+int main()
+{
+  for (const auto& i, 21)  // { dg-error "has no initializer|expected" }
+    i;
+}