[Bug c++/119763] [modules] Declarations in extern "C++" incorrectly treated as attached to named module

[nshead at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119763

Nathaniel Shead <nshead at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Blocks|                            |103524
             Status|UNCONFIRMED                 |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |nshead at gcc dot 
gnu.org
   Last reconfirmed|                            |2025-04-12

--- Comment #1 from Nathaniel Shead <nshead at gcc dot gnu.org> ---
The following (untested) patch should fix the issue:

diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index 927f51b116b..0a52d333b8a 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -7539,7 +7539,7 @@ inline bool module_has_cmi_p ()
 inline bool module_purview_p ()
 { return module_kind & MK_PURVIEW; }
 inline bool module_attach_p ()
-{ return module_kind & MK_ATTACH; }
+{ return (module_kind & MK_ATTACH) && current_lang_depth () == 0; }

 inline bool named_module_purview_p ()
 { return named_module_p () && module_purview_p (); }


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103524
[Bug 103524] [meta-bug] modules issue