Handle errors in both args of va_arg

2016-08-29  Tom de Vries  <tom@codesourcery.com>

	PR c/77398
	* c-common.c (build_va_arg): Add first argument error.  Build va_arg
	with error_mark_node as va_list instead of with illegal va_list.

	* gimplify.c (gimplify_va_arg_expr): Replace first argument type error
	with assert.

	* g++.dg/ext/va-arg1.C: Add error check for illegal first argument.

From-SVN: r239827

gcc/ChangeLog

@@ -1,3 +1,9 @@
+2016-08-29  Tom de Vries  <tom@codesourcery.com>
+
+	PR c/77398
+	* gimplify.c (gimplify_va_arg_expr): Replace first argument type error
+	with assert.
+
 2016-08-29  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* Makefile.in (gcov-iov.h): Add dummy recipe.

gcc/c-family/ChangeLog

@@ -1,3 +1,9 @@
+2016-08-29  Tom de Vries  <tom@codesourcery.com>
+
+	PR c/77398
+	* c-common.c (build_va_arg): Add first argument error.  Build va_arg
+	with error_mark_node as va_list instead of with illegal va_list.
+
 2016-08-25  Marek Polacek  <polacek@redhat.com>
 	    David Malcolm  <dmalcolm@redhat.com>
 

gcc/c-family/c-common.c

@@ -5806,16 +5806,19 @@ build_va_arg (location_t loc, tree expr, tree type)
 {
   tree va_type = TREE_TYPE (expr);
   tree canon_va_type = (va_type == error_mark_node
-			? NULL_TREE
+			? error_mark_node
 			: targetm.canonical_va_list_type (va_type));
 
   if (va_type == error_mark_node
       || canon_va_type == NULL_TREE)
     {
+      if (canon_va_type == NULL_TREE)
+	error_at (loc, "first argument to %<va_arg%> not of type %<va_list%>");
+
       /* Let's handle things neutrallly, if expr:
 	 - has undeclared type, or
 	 - is not an va_list type.  */
-      return build_va_arg_1 (loc, type, expr);
+      return build_va_arg_1 (loc, type, error_mark_node);
     }
 
   if (TREE_CODE (canon_va_type) != ARRAY_TYPE)

gcc/gimplify.c

@@ -11959,12 +11959,7 @@ gimplify_va_arg_expr (tree *expr_p, gimple_seq *pre_p,
   if (have_va_type == error_mark_node)
     return GS_ERROR;
   have_va_type = targetm.canonical_va_list_type (have_va_type);
-
+  gcc_assert (have_va_type != NULL_TREE);
-  if (have_va_type == NULL_TREE)
-    {
-      error_at (loc, "first argument to %<va_arg%> not of type %<va_list%>");
-      return GS_ERROR;
-    }
 
   /* Generate a diagnostic for requesting data of a type that cannot
      be passed through `...' due to type promotion at the call site.  */

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2016-08-29  Tom de Vries  <tom@codesourcery.com>
+
+	PR c/77398
+	* g++.dg/ext/va-arg1.C: Add error check for illegal first argument.
+
 2016-08-29  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gcc.dg/ipa/iinline-attr.c: XFAIL on Visium.

gcc/testsuite/g++.dg/ext/va-arg1.C

@@ -4,5 +4,7 @@ struct A {};
 
 void foo()
 {
-  ++__builtin_va_arg(0, A); // { dg-error "operand type is 'A'" }
+  ++__builtin_va_arg (0, A);
+  // { dg-error "operand type is 'A'" "" {target *-*-*} "7" }
+  // { dg-error "first argument to 'va_arg' not of type 'va_list'" "" {target *-*-*} "7" }
 }