re PR c++/77321 (crash in warn_for_memset)

	PR c++/77321
	* c-common.c (warn_for_memset): Check type for null.

	* g++.dg/cpp1y/pr77321.C: New test.

From-SVN: r239676

gcc/c-family/ChangeLog

+2016-08-22  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/77321
+	* c-common.c (warn_for_memset): Check type for null.
+
 2016-08-22  Joseph Myers  <joseph@codesourcery.com>
 
 	* c-family/c-cppbuiltin.c (c_cpp_builtins): Check _FloatN and

gcc/c-family/c-common.c

@@ -11991,7 +11991,7 @@ warn_for_memset (location_t loc, tree arg0, tree arg2,
       if (TREE_CODE (arg0) == ADDR_EXPR)
 	arg0 = TREE_OPERAND (arg0, 0);
       tree type = TREE_TYPE (arg0);
-      if (TREE_CODE (type) == ARRAY_TYPE)
+      if (type != NULL_TREE && TREE_CODE (type) == ARRAY_TYPE)
 	{
 	  tree elt_type = TREE_TYPE (type);
 	  tree domain = TYPE_DOMAIN (type);

gcc/testsuite/ChangeLog

+2016-08-22  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/77321
+	* g++.dg/cpp1y/pr77321.C: New test.
+
 2016-08-22  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	PR fortran/60774

gcc/testsuite/g++.dg/cpp1y/pr77321.C

+// PR c++/77321
+// { dg-do compile { target c++14 } }
+// { dg-options "-Wall" }
+
+extern "C" void *memset (void *, int, __SIZE_TYPE__);
+extern "C" void *malloc(__SIZE_TYPE__);
+
+struct S {
+    char *a;
+};
+
+template <typename T>
+void Test(T & Obj) {
+    auto && a(Obj.a);
+    a = (char*)::malloc(1024 * 1024);
+    ::memset(a + 28, 'X', 6);
+}
+
+int main()
+{
+  S d;
+  Test(d);
+  return 0;
+}