re PR c++/70323 (missing error on integer overflow in constexpr function result converted to bool)

	PR c++/70323
	* constexpr.c (cxx_eval_constant_expression): Diagnose overflow
	on TREE_OVERFLOW constants.

	* g++.dg/cpp0x/constexpr-70323.C: New test.

From-SVN: r234438

gcc/cp/ChangeLog

 2016-03-23  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c++/70323
+	* constexpr.c (cxx_eval_constant_expression): Diagnose overflow
+	on TREE_OVERFLOW constants.
+
 	PR c++/70376
 	* cp-gimplify.c (genericize_omp_for_stmt): Don't walk OMP_FOR_CLAUSES
 	for OMP_TASKLOOP here.

gcc/cp/constexpr.c

@@ -3321,8 +3321,13 @@ cxx_eval_constant_expression (const constexpr_ctx *ctx, tree t,
     }
   if (CONSTANT_CLASS_P (t))
     {
-      if (TREE_OVERFLOW (t) && (!flag_permissive || ctx->quiet))
-	*overflow_p = true;
+      if (TREE_OVERFLOW (t))
+	{
+	  if (!ctx->quiet)
+	    permerror (input_location, "overflow in constant expression");
+	  if (!flag_permissive || ctx->quiet)
+	    *overflow_p = true;
+	}
       return t;
     }
 

gcc/testsuite/ChangeLog

+2016-03-23  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/70323
+	* g++.dg/cpp0x/constexpr-70323.C: New test.
+
 2016-03-23  Alexandre Oliva  <aoliva@redhat.com>
 	    Jason Merrill  <jason@redhat.com>
 	    Jakub Jelinek  <jakub@redhat.com>

gcc/testsuite/g++.dg/cpp0x/constexpr-70323.C

+// PR c++/70323
+// { dg-do compile { target c++11 } }
+
+constexpr int overflow_if_0 (int i) { return __INT_MAX__ + !i; }
+constexpr int overflow_if_1 (int i) { return __INT_MAX__ + i; }
+
+constexpr bool i0_0 = overflow_if_0 (0);   // { dg-error "overflow in constant expression" }
+constexpr bool i0_1 = overflow_if_0 (1);
+constexpr bool i1_0 = overflow_if_1 (0);
+constexpr bool i1_1 = overflow_if_1 (1);   // { dg-error "overflow in constant expression" }