From 3e0768d2ffde3f20c5baa92d33869f0c196245c4 Mon Sep 17 00:00:00 2001 From: Nathaniel Shead Date: Thu, 27 Mar 2025 00:23:24 +1100 Subject: [PATCH] c++/modules: Fix tsubst of global module friend classes [PR118920] When doing tsubst_friend_class, we need to first check if any imported module has already created a (hidden) declaration for the class so that we don't end up with conflicting declarations. Currently we do this using DECL_MODULE_IMPORT_P, but this is not set in cases where the class is in the global module and matches an existing GM declaration we've seen (via an include, for example). This patch fixes this by checking DECL_MODULE_ENTITY_P instead, which is set on all entities that have been seen from a module import. We also use the 'for_mangle' version of get_originating_module so that we don't treat imported GM entities as attached to the module we imported them from. And rename that parameter to something more general. And dump_module_suffix is another place where we want to treat global module entities as not coming from a module. PR c++/118920 gcc/cp/ChangeLog: * name-lookup.cc (lookup_imported_hidden_friend): Check for module entity rather than just module import. * module.cc (get_originating_module): Rename for_mangle parm to global_m1. * error.cc (dump_module_suffix): Don't decorate global module decls. gcc/testsuite/ChangeLog: * g++.dg/modules/tpl-friend-17.h: New test. * g++.dg/modules/tpl-friend-17_a.C: New test. * g++.dg/modules/tpl-friend-17_b.C: New test. Signed-off-by: Nathaniel Shead Co-authored-by: Jason Merrill --- gcc/cp/error.cc | 3 ++- gcc/cp/module.cc | 12 ++++++++---- gcc/cp/name-lookup.cc | 10 +++++----- gcc/testsuite/g++.dg/modules/tpl-friend-17.h | 8 ++++++++ gcc/testsuite/g++.dg/modules/tpl-friend-17_a.C | 9 +++++++++ gcc/testsuite/g++.dg/modules/tpl-friend-17_b.C | 11 +++++++++++ 6 files changed, 43 insertions(+), 10 deletions(-) create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-17.h create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-17_a.C create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-17_b.C diff --git a/gcc/cp/error.cc b/gcc/cp/error.cc index 72e16958548..ec7527e96d1 100644 --- a/gcc/cp/error.cc +++ b/gcc/cp/error.cc @@ -308,7 +308,8 @@ dump_module_suffix (cxx_pretty_printer *pp, tree decl) return; } - if (unsigned m = get_originating_module (decl)) + int m = get_originating_module (decl, /*global=-1*/true); + if (m > 0) if (const char *n = module_name (m, false)) { pp_character (pp, '@'); diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc index 2cded878c64..f2d64bf3b5f 100644 --- a/gcc/cp/module.cc +++ b/gcc/cp/module.cc @@ -20371,20 +20371,24 @@ get_originating_module_decl (tree decl) return decl; } +/* If DECL is imported, return which module imported it, or 0 for the current + module. Except that if GLOBAL_M1, return -1 for decls attached to the + global module. */ + int -get_originating_module (tree decl, bool for_mangle) +get_originating_module (tree decl, bool global_m1) { tree owner = get_originating_module_decl (decl); tree not_tmpl = STRIP_TEMPLATE (owner); if (!DECL_LANG_SPECIFIC (not_tmpl)) - return for_mangle ? -1 : 0; + return global_m1 ? -1 : 0; - if (for_mangle && !DECL_MODULE_ATTACH_P (not_tmpl)) + if (global_m1 && !DECL_MODULE_ATTACH_P (not_tmpl)) return -1; int mod = !DECL_MODULE_IMPORT_P (not_tmpl) ? 0 : get_importing_module (owner); - gcc_checking_assert (!for_mangle || !(*modules)[mod]->is_header ()); + gcc_checking_assert (!global_m1 || !(*modules)[mod]->is_header ()); return mod; } diff --git a/gcc/cp/name-lookup.cc b/gcc/cp/name-lookup.cc index 742e5d289dc..7f1ee869d52 100644 --- a/gcc/cp/name-lookup.cc +++ b/gcc/cp/name-lookup.cc @@ -4568,7 +4568,7 @@ lookup_imported_hidden_friend (tree friend_tmpl) tree inner = DECL_TEMPLATE_RESULT (friend_tmpl); if (!DECL_LANG_SPECIFIC (inner) - || !DECL_MODULE_IMPORT_P (inner)) + || !DECL_MODULE_ENTITY_P (inner)) return NULL_TREE; lazy_load_pendings (friend_tmpl); @@ -4578,16 +4578,16 @@ lookup_imported_hidden_friend (tree friend_tmpl) if (!bind) return NULL_TREE; - /* We're only interested in declarations coming from the same module - of the friend class we're attempting to instantiate. */ - int m = get_originating_module (friend_tmpl); + /* We're only interested in declarations attached to the same module + as the friend class we're attempting to instantiate. */ + int m = get_originating_module (friend_tmpl, /*global=-1*/true); gcc_assert (m != 0); /* There should be at most one class template from the module we're looking for, return it. */ for (ovl_iterator iter (bind); iter; ++iter) if (DECL_CLASS_TEMPLATE_P (*iter) - && get_originating_module (*iter) == m) + && get_originating_module (*iter, true) == m) return *iter; return NULL_TREE; diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-17.h b/gcc/testsuite/g++.dg/modules/tpl-friend-17.h new file mode 100644 index 00000000000..429ab3d5977 --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-17.h @@ -0,0 +1,8 @@ +// PR c++/118920 + +template struct unique_ptr { + template friend class out_ptr_t; +}; +template struct shared_ptr { + template friend class out_ptr_t; +}; diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-17_a.C b/gcc/testsuite/g++.dg/modules/tpl-friend-17_a.C new file mode 100644 index 00000000000..7c5a3ac7ed1 --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-17_a.C @@ -0,0 +1,9 @@ +// PR c++/118920 +// { dg-additional-options "-fmodules" } +// { dg-module-cmi M } + +module; +#include "tpl-friend-17.h" +export module M; +unique_ptr s; +export template void foo() { shared_ptr u; } diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-17_b.C b/gcc/testsuite/g++.dg/modules/tpl-friend-17_b.C new file mode 100644 index 00000000000..33586e662ef --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-17_b.C @@ -0,0 +1,11 @@ +// PR c++/118920 +// { dg-additional-options "-fmodules" } + +#include "tpl-friend-17.h" +import M; + +int main() { + // instantiating shared_ptr should find previously generated + // out_ptr_t template from the unique_ptr instantiation + foo(); +}