https://gcc.gnu.org/g:664bd76a23def2d458bb3c531486b4c220f29c11
commit r15-6819-g664bd76a23def2d458bb3c531486b4c220f29c11
Author: Jason Merrill <ja...@redhat.com>
Date: Fri Jan 10 18:00:20 2025 -0500
c++: modules and function attributes
30_threads/stop_token/stop_source/109339.cc was failing because we weren't
representing attribute access on the METHOD_TYPE for _Stop_state_ref.
The modules code expected attributes to appear on tt_variant_type and not
on tt_derived_type, but that's backwards since build_type_attribute_variant
gives a type with attributes its own TYPE_MAIN_VARIANT.
gcc/cp/ChangeLog:
* module.cc (trees_out::type_node): Write attributes for
tt_derived_type, not tt_variant_type.
(trees_in::tree_node): Likewise for reading.
gcc/testsuite/ChangeLog:
* g++.dg/modules/attrib-2_a.C: New test.
* g++.dg/modules/attrib-2_b.C: New test.
Diff:
---
gcc/cp/module.cc | 17 +++++++++++++----
gcc/testsuite/g++.dg/modules/attrib-2_a.C | 12 ++++++++++++
gcc/testsuite/g++.dg/modules/attrib-2_b.C | 9 +++++++++
3 files changed, 34 insertions(+), 4 deletions(-)
diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc
index 321d4164a6a7..c932c4d0a90d 100644
--- a/gcc/cp/module.cc
+++ b/gcc/cp/module.cc
@@ -9189,7 +9189,10 @@ trees_out::type_node (tree type)
tree_node (raises);
}
- tree_node (TYPE_ATTRIBUTES (type));
+ /* build_type_attribute_variant creates a new TYPE_MAIN_VARIANT, so
+ variants should all have the same set of attributes. */
+ gcc_checking_assert (TYPE_ATTRIBUTES (type)
+ == TYPE_ATTRIBUTES (TYPE_MAIN_VARIANT (type)));
if (streaming_p ())
{
@@ -9406,6 +9409,8 @@ trees_out::type_node (tree type)
break;
}
+ tree_node (TYPE_ATTRIBUTES (type));
+
/* We may have met the type during emitting the above. */
if (ref_node (type) != WK_none)
{
@@ -10090,6 +10095,13 @@ trees_in::tree_node (bool is_use)
break;
}
+ /* In the exporting TU, a derived type with attributes was built by
+ build_type_attribute_variant as a distinct copy, with itself as
+ TYPE_MAIN_VARIANT. We repeat that on import to get the version
+ without attributes as TYPE_CANONICAL. */
+ if (tree attribs = tree_node ())
+ res = cp_build_type_attribute_variant (res, attribs);
+
int tag = i ();
if (!tag)
{
@@ -10133,9 +10145,6 @@ trees_in::tree_node (bool is_use)
TYPE_USER_ALIGN (res) = true;
}
- if (tree attribs = tree_node ())
- res = cp_build_type_attribute_variant (res, attribs);
-
int quals = i ();
if (quals >= 0 && !get_overrun ())
res = cp_build_qualified_type (res, quals);
diff --git a/gcc/testsuite/g++.dg/modules/attrib-2_a.C
b/gcc/testsuite/g++.dg/modules/attrib-2_a.C
new file mode 100644
index 000000000000..96f667ceec8c
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/attrib-2_a.C
@@ -0,0 +1,12 @@
+// { dg-additional-options "-fmodules -Wno-global-module" }
+// { dg-module-cmi M }
+
+export module M;
+
+export
+{
+ struct A { int i; };
+
+ __attribute ((access (none, 1)))
+ void f(const A&);
+}
diff --git a/gcc/testsuite/g++.dg/modules/attrib-2_b.C
b/gcc/testsuite/g++.dg/modules/attrib-2_b.C
new file mode 100644
index 000000000000..c12ad117ce4f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/attrib-2_b.C
@@ -0,0 +1,9 @@
+// { dg-additional-options "-fmodules -Wmaybe-uninitialized" }
+
+import M;
+
+int main()
+{
+ A a;
+ f(a);
+}
