On Fri, Feb 02, 2018 at 03:13:21PM -0500, Jason Merrill wrote:
> > Or should I change the switch body to do other kind = overrides?
>
> I think we want to avoid clobbering NON_LVALUE_EXPR location wrappers, too.
>
> This has gotten large enough that it should break out into its own function.
>
> OK with those changes.
So like this? Bootstrapped/regtested on x86_64-linux and i686-linux.
2018-02-06 Jakub Jelinek <ja...@redhat.com>
PR c++/84082
* parser.c (cp_parser_dot_deref_incomplete): New function.
(cp_parser_postfix_dot_deref_expression): Use it.
* g++.dg/template/incomplete11.C: New test.
* g++.dg/parse/crash67.C: Expect an incomplete type diagnostics too.
--- gcc/cp/parser.c.jj 2018-01-31 19:07:35.401199026 +0100
+++ gcc/cp/parser.c 2018-02-03 19:08:37.828664789 +0100
@@ -7387,6 +7387,63 @@ cp_parser_postfix_open_square_expression
return postfix_expression;
}
+/* A subroutine of cp_parser_postfix_dot_deref_expression. Handle dot
+ dereference of incomplete type, returns true if error_mark_node should
+ be returned from caller, otherwise adjusts *SCOPE, *POSTFIX_EXPRESSION
+ and *DEPENDENT_P. */
+
+bool
+cp_parser_dot_deref_incomplete (tree *scope, cp_expr *postfix_expression,
+ bool *dependent_p)
+{
+ /* In a template, be permissive by treating an object expression
+ of incomplete type as dependent (after a pedwarn). */
+ diagnostic_t kind = (processing_template_decl
+ && MAYBE_CLASS_TYPE_P (*scope) ? DK_PEDWARN : DK_ERROR);
+
+ switch (TREE_CODE (*postfix_expression))
+ {
+ case CAST_EXPR:
+ case REINTERPRET_CAST_EXPR:
+ case CONST_CAST_EXPR:
+ case STATIC_CAST_EXPR:
+ case DYNAMIC_CAST_EXPR:
+ case IMPLICIT_CONV_EXPR:
+ case VIEW_CONVERT_EXPR:
+ kind = DK_ERROR;
+ break;
+ case NON_LVALUE_EXPR:
+ if (location_wrapper_p (*postfix_expression))
+ kind = DK_ERROR;
+ break;
+ case OVERLOAD:
+ /* Don't emit any diagnostic for OVERLOADs. */
+ kind = DK_IGNORED;
+ break;
+ default:
+ /* Avoid clobbering e.g. DECLs. */
+ if (!EXPR_P (*postfix_expression))
+ kind = DK_ERROR;
+ break;
+ }
+
+ if (kind == DK_IGNORED)
+ return false;
+
+ location_t exploc = location_of (*postfix_expression);
+ cxx_incomplete_type_diagnostic (exploc, *postfix_expression, *scope, kind);
+ if (!MAYBE_CLASS_TYPE_P (*scope))
+ return true;
+ if (kind == DK_ERROR)
+ *scope = *postfix_expression = error_mark_node;
+ else if (processing_template_decl)
+ {
+ *dependent_p = true;
+ *scope = TREE_TYPE (*postfix_expression) = NULL_TREE;
+ }
+ return false;
+}
+
/* A subroutine of cp_parser_postfix_expression that also gets hijacked
by cp_parser_builtin_offsetof. We're looking for
@@ -7451,26 +7508,9 @@ cp_parser_postfix_dot_deref_expression (
{
scope = complete_type (scope);
if (!COMPLETE_TYPE_P (scope)
- /* Avoid clobbering e.g. OVERLOADs or DECLs. */
- && EXPR_P (postfix_expression))
- {
- /* In a template, be permissive by treating an object expression
- of incomplete type as dependent (after a pedwarn). */
- diagnostic_t kind = (processing_template_decl
- && MAYBE_CLASS_TYPE_P (scope)
- ? DK_PEDWARN
- : DK_ERROR);
- cxx_incomplete_type_diagnostic
- (location_of (postfix_expression),
- postfix_expression, scope, kind);
- if (!MAYBE_CLASS_TYPE_P (scope))
- return error_mark_node;
- if (processing_template_decl)
- {
- dependent_p = true;
- scope = TREE_TYPE (postfix_expression) = NULL_TREE;
- }
- }
+ && cp_parser_dot_deref_incomplete (&scope, &postfix_expression,
+ &dependent_p))
+ return error_mark_node;
}
if (!dependent_p)
--- gcc/testsuite/g++.dg/template/incomplete11.C.jj 2018-02-03
17:56:10.536083614 +0100
+++ gcc/testsuite/g++.dg/template/incomplete11.C 2018-02-03
17:56:10.536083614 +0100
@@ -0,0 +1,10 @@
+// PR c++/84082
+// { dg-do compile }
+// { dg-options "" }
+
+struct A;
+
+template<typename> void foo()
+{
+ static int a[A().operator=(A())]; // { dg-error "invalid use of
incomplete type 'struct A'" }
+}
--- gcc/testsuite/g++.dg/parse/crash67.C.jj 2018-01-31 19:07:33.571220455
+0100
+++ gcc/testsuite/g++.dg/parse/crash67.C 2018-02-03 17:56:10.536083614
+0100
@@ -3,4 +3,4 @@
class x0;
template <x1> x2() { // { dg-error "declared|type" }
-x0 x3 = x3. // { dg-error "expected" }
+x0 x3 = x3. // { dg-error "expected|incomplete type" }
Jakub
