Re: [PATCH] c++ modules: ICE with class NTTP argument [PR100616]

[Nathan Sidwell via Gcc-patches]

On 9/28/22 10:42, Patrick Palka wrote:
On Tue, 27 Sep 2022, Nathan Sidwell wrote:
On 9/26/22 15:05, Patrick Palka wrote:
On Mon, 26 Sep 2022, Patrick Palka wrote:

On Mon, 26 Sep 2022, Nathan Sidwell wrote:



       return decl;
@@ -29150,9 +29151,10 @@ finish_concept_definition (cp_expr id, tree init)
   static tree
   listify (tree arg)
   {
-  tree std_init_list = get_namespace_binding (std_node,
init_list_identifier);
+  tree std_init_list = lookup_qualified_name (std_node,
init_list_identifier);
   -  if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
+  if (std_init_list == error_mark_node
+      || !DECL_CLASS_TEMPLATE_P (std_init_list))
       {
         gcc_rich_location richloc (input_location);
         maybe_add_include_fixit (&richloc, "<initializer_list>", false);

What do you think about this independent change to use
lookup_qualified_name instead of get_namespace_binding in listify so
that the lookup for std::initializer_list is import-aware, which seems
to fix PR102576?

Yes, that looks right to me, thanks!  (I think it'll also fix a 
potential future problem if we ever have:

namespace std {
inline namespace v2 {
template <stuff> class initializer_list {...};
}}


diff --git a/gcc/testsuite/g++.dg/modules/pr100616_a.C
b/gcc/testsuite/g++.dg/modules/pr100616_a.C
new file mode 100644
index 00000000000..788af2eb533
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr100616_a.C
@@ -0,0 +1,8 @@
+// PR c++/100616
+// { dg-additional-options "-std=c++20 -fmodules-ts" }
+// { dg-module-cmi pr100616 }
+export module pr100616;
+
+template<auto> struct C { };
+struct A { };
+C<A{}> c1;
diff --git a/gcc/testsuite/g++.dg/modules/pr100616_b.C
b/gcc/testsuite/g++.dg/modules/pr100616_b.C
new file mode 100644
index 00000000000..fc89cd08ac5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr100616_b.C
@@ -0,0 +1,8 @@
+// PR c++/100616
+// { dg-additional-options "-std=c++20 -fmodules-ts" }
+module pr100616;
+
+C<A{}> c2;
+
+using type = decltype(c1);
+using type = decltype(c2);
diff --git a/gcc/testsuite/g++.dg/modules/pr102576_a.H
b/gcc/testsuite/g++.dg/modules/pr102576_a.H
new file mode 100644
index 00000000000..87ba9b52031
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr102576_a.H
@@ -0,0 +1,5 @@
+// PR c++/102576
+// { dg-additional-options -fmodule-header }
+// { dg-module-cmi {} }
+
+#include <initializer_list>
diff --git a/gcc/testsuite/g++.dg/modules/pr102576_b.C
b/gcc/testsuite/g++.dg/modules/pr102576_b.C
new file mode 100644
index 00000000000..10251ed5304
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr102576_b.C
@@ -0,0 +1,9 @@
+// PR c++/102576
+// { dg-additional-options -fmodules-ts }
+
+import "pr102576_a.H";
+
+int main() {
+  for (int i : {1, 2, 3})
+    ;
+}

--
Nathan Sidwell


--
Nathan Sidwell