From 8f03e02f36105e7b3c7d21ce2368f3e3147d091a Mon Sep 17 00:00:00 2001
From: Jakub Jelinek <jakub@redhat.com>
Date: Fri, 16 Sep 2016 22:25:17 +0200
Subject: [PATCH] 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                             |  4 ++++
 gcc/cp/error.c                               | 15 +++++++--------
 gcc/testsuite/ChangeLog                      |  3 +++
 gcc/testsuite/g++.dg/cpp0x/constexpr-77482.C |  6 ++++++
 4 files changed, 20 insertions(+), 8 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/constexpr-77482.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 0c7d351..9d74bdb 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 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.
diff --git a/gcc/cp/error.c b/gcc/cp/error.c
index 88049ee..ca7360f 100644
--- a/gcc/cp/error.c
+++ b/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);
     }
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 88d3296..dfcccf7 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 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.
diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-77482.C b/gcc/testsuite/g++.dg/cpp0x/constexpr-77482.C
new file mode 100644
index 0000000..6f5c916
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-77482.C
@@ -0,0 +1,6 @@
+// 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" }
-- 
2.7.4