Re: [PATCH] c++: Fix up ICE when cplus_decl_attributes is called with error_mark_node attributes [PR104668]

[Jakub Jelinek via Gcc-patches]

On Fri, Mar 25, 2022 at 07:48:33PM +0100, Jakub Jelinek wrote:
> We then wouldn't propagate TREE_DEPRECATED/TREE_UNAVAILABLE from templates
> to their instantiations and wouldn't diagnose static data members in OpenMP
> declare target.
> But perhaps that is fine, with error_mark_attribute it is error recovery
> anyway.
> Can the splice_template_attributes change stay too, or just
> change cplus_decl_attributes (add it to the early out, remove from other
> spots in the function)?

So like (or without the first hunk):

2022-03-25  Jakub Jelinek  <ja...@redhat.com>

        PR c++/104668
        * decl2.cc (splice_template_attributes): Return NULL if *p is
        error_mark_node.
        (cplus_decl_attributes): Return early if attributes is
        error_mark_node.  Don't check that later.

        * g++.dg/cpp0x/pr104668.C: New test.

--- gcc/cp/decl2.cc.jj  2022-03-09 09:09:55.415843331 +0100
+++ gcc/cp/decl2.cc     2022-03-25 19:54:12.454749089 +0100
@@ -1336,7 +1336,7 @@ splice_template_attributes (tree *attr_p
   tree late_attrs = NULL_TREE;
   tree *q = &late_attrs;
 
-  if (!p)
+  if (!p || *p == error_mark_node)
     return NULL_TREE;
 
   for (; *p; )
@@ -1631,7 +1631,7 @@ void
 cplus_decl_attributes (tree *decl, tree attributes, int flags)
 {
   if (*decl == NULL_TREE || *decl == void_type_node
-      || *decl == error_mark_node)
+      || *decl == error_mark_node || attributes == error_mark_node)
     return;
 
   /* Add implicit "omp declare target" attribute if requested.  */
@@ -1668,7 +1668,7 @@ cplus_decl_attributes (tree *decl, tree
 
   cp_check_const_attributes (attributes);
 
-  if ((flag_openmp || flag_openmp_simd) && attributes != error_mark_node)
+  if (flag_openmp || flag_openmp_simd)
     {
       bool diagnosed = false;
       for (tree *pa = &attributes; *pa; )
--- gcc/testsuite/g++.dg/cpp0x/pr104668.C.jj    2022-03-25 17:25:42.280068058 
+0100
+++ gcc/testsuite/g++.dg/cpp0x/pr104668.C       2022-03-25 17:24:44.862881444 
+0100
@@ -0,0 +1,13 @@
+// PR c++/104668
+// { dg-do compile { target c++11 } }
+// { dg-excess-errors "" }
+
+template <class... Ts>
+void sink(Ts...);
+template <class... Ts>
+void f(Ts...) {
+  sink([] { struct alignas:Ts) S {}; }...); }
+}
+int main() {
+  f(0);
+}


        Jakub