c++/modules: Don't build STAT_HACKs for current TU namespace bindings [PR122995]

The issue in the PR is that we're checking if the binding entity for the
current TU matches the namespace we're pushing.  In this case the slot
however is a STAT_HACK we created during 'maybe_record_mergeable_decl'
to indicate that the binding entity contains a global module binding.

Adding '|| (STAT_HACK_P ((tree) slot) && STAT_DECL ((tree) slot) == ns)'
should fix the assertion, but I think we want to just not build the
STAT_HACK for namespaces, as they'll always be global module regardless,
and cannot match with any other declaration, so there's no need for the
special flag.

	PR c++/122995

gcc/cp/ChangeLog:

	* name-lookup.cc (maybe_record_mergeable_decl): Don't build a
	STAT_HACK for namespaces.

gcc/testsuite/ChangeLog:

	* g++.dg/modules/namespace-17_a.C: New test.
	* g++.dg/modules/namespace-17_b.C: New test.

Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>

diff --git a/gcc/cp/name-lookup.cc b/gcc/cp/name-lookup.cc
index 4c07fd40f644b824e2a1c8219dd5e6ac6357dca1..8fa5a0c246d704f52f5d112d73b6d3842300bdb7 100644 (file)
--- a/gcc/cp/name-lookup.cc
+++ b/gcc/cp/name-lookup.cc
@@ -3791,7 +3791,9 @@ maybe_record_mergeable_decl (tree *slot, tree name, tree decl)
     (slot, name, is_attached ? BINDING_SLOT_PARTITION : BINDING_SLOT_GLOBAL,
      true);
 
-  if (!is_attached)
+  /* A namespace is always global module so there's no need to mark
+     the current binding slot as such.  */
+  if (!is_attached && TREE_CODE (decl) != NAMESPACE_DECL)
     {
       binding_slot &orig
        = BINDING_VECTOR_CLUSTER (*slot, 0).slots[BINDING_SLOT_CURRENT];

diff --git a/gcc/testsuite/g++.dg/modules/namespace-17_a.C b/gcc/testsuite/g++.dg/modules/namespace-17_a.C
new file mode 100644 (file)
index 0000000..e78a824
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/namespace-17_a.C
@@ -0,0 +1,8 @@
+// PR c++/122995
+// { dg-additional-options "-fmodules" }
+// { dg-module-cmi bug2 }
+
+export module bug2;
+namespace N {
+  namespace C { struct r3_cpo; } export extern inline C::r3_cpo const r3;
+}

diff --git a/gcc/testsuite/g++.dg/modules/namespace-17_b.C b/gcc/testsuite/g++.dg/modules/namespace-17_b.C
new file mode 100644 (file)
index 0000000..33d56db
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/namespace-17_b.C
@@ -0,0 +1,10 @@
+// PR c++/122995
+// { dg-additional-options "-fmodules" }
+// { dg-module-cmi bug }
+
+export module bug;
+import bug2;
+namespace N {
+  namespace C { struct r1_cpo; } export extern inline C::r1_cpo const r1;
+  namespace C { struct r2_cpo; } export extern inline C::r2_cpo const r2;
+}