re PR c++/77482 (Segfault when compiling ill-formed constexpr code)

	PR c++/77482
	* error.c (dump_simple_decl): Only check DECL_DECLARED_CONCEPT_P
	if DECL_LANG_SPECIFIC is non-NULL.  Fix up formatting.

	* g++.dg/cpp0x/constexpr-77482.C: New test.

From-SVN: r240198

gcc/cp/ChangeLog

 2016-09-16  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c++/77482
+	* error.c (dump_simple_decl): Only check DECL_DECLARED_CONCEPT_P
+	if DECL_LANG_SPECIFIC is non-NULL.  Fix up formatting.
+
 	PR c++/77338
 	* constexpr.c (cxx_eval_constant_expression) <case PARM_DECL>: Only
 	call is_really_empty_class on complete types.

gcc/cp/error.c

@@ -959,14 +959,13 @@ dump_simple_decl (cxx_pretty_printer *pp, tree t, tree type, int flags)
 {
   if (flags & TFF_DECL_SPECIFIERS)
     {
-      if (VAR_P (t)
-	  && DECL_DECLARED_CONSTEXPR_P (t))
-            {
-              if (DECL_DECLARED_CONCEPT_P (t))
-                pp_cxx_ws_string (pp, "concept");
-              else
-		pp_cxx_ws_string (pp, "constexpr");
-            }
+      if (VAR_P (t) && DECL_DECLARED_CONSTEXPR_P (t))
+        {
+	  if (DECL_LANG_SPECIFIC (t) && DECL_DECLARED_CONCEPT_P (t))
+	    pp_cxx_ws_string (pp, "concept");
+	  else
+	    pp_cxx_ws_string (pp, "constexpr");
+	}
       dump_type_prefix (pp, type, flags & ~TFF_UNQUALIFIED_NAME);
       pp_maybe_space (pp);
     }

gcc/testsuite/ChangeLog

 2016-09-16  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c++/77482
+	* g++.dg/cpp0x/constexpr-77482.C: New test.
+
 	PR c++/77379
 	* g++.dg/abi/abi-tag23.C: Adjust scan-assembler regex for differing
 	thunk offsets.

gcc/testsuite/g++.dg/cpp0x/constexpr-77482.C

+// PR c++/77482
+// { dg-do compile { target c++11 } }
+
+constexpr auto x;	// { dg-error "declaration\[^\n\r]*has no initializer" }
+extern struct S s;
+constexpr auto y = s;	// { dg-error "has incomplete type" }