From 133bc698cb8f42e3655fc68fee19c62fd18d98f7 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Thu, 11 Jun 2015 11:45:08 -0400
Subject: [PATCH] re PR c++/66445 (ICE with lambda in stmt expression in a
 template)

	PR c++/66445
	* constexpr.c (potential_constant_expression_1): Handle a
	DECL_EXPR of TYPE_DECL.

From-SVN: r224382
---
 gcc/cp/ChangeLog                      | 4 ++++
 gcc/cp/constexpr.c                    | 5 +++++
 gcc/testsuite/g++.dg/ext/stmtexpr18.C | 7 +++++++
 3 files changed, 16 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/ext/stmtexpr18.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index b6fdc107f6e..23c8deb2283 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 2015-06-11  Jason Merrill  <jason@redhat.com>
 
+	PR c++/66445
+	* constexpr.c (potential_constant_expression_1): Handle a
+	DECL_EXPR of TYPE_DECL.
+
 	PR c++/66450
 	* constexpr.c (cxx_eval_store_expression): Avoid messing up outer
 	ctx->ctor.
diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
index af6b39ecaf5..5dc59a47a88 100644
--- a/gcc/cp/constexpr.c
+++ b/gcc/cp/constexpr.c
@@ -4462,6 +4462,11 @@ potential_constant_expression_1 (tree t, bool want_rval, bool strict,
 	}
       return false;
 
+    case TYPE_DECL:
+    case TAG_DEFN:
+      /* We can see these in statement-expressions.  */
+      return true;
+
     default:
       if (objc_is_property_ref (t))
 	return false;
diff --git a/gcc/testsuite/g++.dg/ext/stmtexpr18.C b/gcc/testsuite/g++.dg/ext/stmtexpr18.C
new file mode 100644
index 00000000000..d9b99bfd265
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/stmtexpr18.C
@@ -0,0 +1,7 @@
+// PR c++/66445
+// { dg-options "" }
+
+template <typename> void foo ()
+{
+  int a = ({ struct A{} b; 42; });
+}
-- 
2.30.2