On Mon, 13 May 2024, Nathaniel Shead wrote:
> > > @@ -11751,9 +11767,16 @@ tsubst_friend_class (tree friend_tmpl, tree args)
> > > if (tmpl != error_mark_node)
> > > {
> > > /* The new TMPL is not an instantiation of anything, so we
> > > - forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE
> > > + forget its origins. It is also not a specialization of
> > > + anything. We don't reset CLASSTYPE_TI_TEMPLATE
> > > for the new type because that is supposed to be the
> > > corresponding template decl, i.e., TMPL. */
> > > + spec_entry elt;
> > > + elt.tmpl = friend_tmpl;
> > > + elt.args = CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl));
> > > + elt.spec = TREE_TYPE (tmpl);
> > > + type_specializations->remove_elt (&elt);
> >
> > For GCC 14.2 let's guard this with if (modules_p ()); for GCC 15 it can be
> > unconditional. OK.
> >
> > Jason
> >
>
> I'm looking to backport this patch to GCC 14 now that it's been on trunk
> some time. Here's the patch I'm aiming to add (squashed with the
> changes from r15-220-gec2365e07537e8) after cherrypicking the
> prerequisite commit r15-58-g2faf040335f9b4; is this OK?
>
> Or should I keep it as two separate commits to make the cherrypicking
> more obvious? Not entirely sure on the etiquette around this.
Since the first patch "only" causes sporadic testsuite failures (and
doesn't e.g. break bootstrap or anything serious like that), I reckon
it'd be fine to keep them as separate commits? Not sure either.
>
> Bootstrapped and regtested on x86_64-pc-linux-gnu on top of the
> releases/gcc-14 branch.
>
> -- >8 --
>
> This patch fixes a number of issues with the handling of temploid friend
> declarations.
>
> The primary issue is that instantiations of friend declarations should
> attach the declaration to the same module as the befriending class, by
> [module.unit] p7.1 and [temp.friend] p2; this could be a different
> module from the current TU, and so needs special handling.
>
> The other main issue here is that we can't assume that just because name
> lookup didn't find a definition for a hidden class template, that it
> doesn't exist at all: it could be a non-exported entity that we've
> nevertheless streamed in from an imported module. We need to ensure
> that when instantiating template friend classes that we return the same
> TEMPLATE_DECL that we got from our imports, otherwise we will get later
> issues with 'duplicate_decls' (rightfully) complaining that they're
> different when trying to merge.
>
> This doesn't appear necessary for function templates due to the existing
> name lookup handling already finding these hidden declarations.
>
> PR c++/105320
> PR c++/114275
>
> gcc/cp/ChangeLog:
>
> * cp-tree.h (propagate_defining_module): Declare.
> (remove_defining_module): Declare.
> (lookup_imported_hidden_friend): Declare.
> * decl.cc (duplicate_decls): Also check if hidden decls can be
> redeclared in this module. Call remove_defining_module on
> to-be-freed newdecl.
> * module.cc (imported_temploid_friends): New.
> (init_modules): Initialize it.
> (trees_out::decl_value): Write it; don't consider imported
> temploid friends as attached to a module.
> (trees_in::decl_value): Read it for non-discarded decls.
> (get_originating_module_decl): Follow the owning decl for an
> imported temploid friend.
> (propagate_defining_module): New.
> (remove_defining_module): New.
> * name-lookup.cc (get_mergeable_namespace_binding): New.
> (lookup_imported_hidden_friend): New.
> * pt.cc (tsubst_friend_function): Propagate defining module for
> new friend functions.
> (tsubst_friend_class): Lookup imported hidden friends. Check
> for valid module attachment of existing names. Propagate
> defining module for new classes.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/modules/tpl-friend-10_a.C: New test.
> * g++.dg/modules/tpl-friend-10_b.C: New test.
> * g++.dg/modules/tpl-friend-10_c.C: New test.
> * g++.dg/modules/tpl-friend-10_d.C: New test.
> * g++.dg/modules/tpl-friend-11_a.C: New test.
> * g++.dg/modules/tpl-friend-11_b.C: New test.
> * g++.dg/modules/tpl-friend-12_a.C: New test.
> * g++.dg/modules/tpl-friend-12_b.C: New test.
> * g++.dg/modules/tpl-friend-12_c.C: New test.
> * g++.dg/modules/tpl-friend-12_d.C: New test.
> * g++.dg/modules/tpl-friend-12_e.C: New test.
> * g++.dg/modules/tpl-friend-12_f.C: New test.
> * g++.dg/modules/tpl-friend-13_a.C: New test.
> * g++.dg/modules/tpl-friend-13_b.C: New test.
> * g++.dg/modules/tpl-friend-13_c.C: New test.
> * g++.dg/modules/tpl-friend-13_d.C: New test.
> * g++.dg/modules/tpl-friend-13_e.C: New test.
> * g++.dg/modules/tpl-friend-13_f.C: New test.
> * g++.dg/modules/tpl-friend-13_g.C: New test.
> * g++.dg/modules/tpl-friend-14_a.C: New test.
> * g++.dg/modules/tpl-friend-14_b.C: New test.
> * g++.dg/modules/tpl-friend-14_c.C: New test.
> * g++.dg/modules/tpl-friend-14_d.C: New test.
> * g++.dg/modules/tpl-friend-9.C: New test.
>
> Signed-off-by: Nathaniel Shead <nathanielosh...@gmail.com>
> Reviewed-by: Jason Merrill <ja...@redhat.com>
> Reviewed-by: Patrick Palka <ppa...@redhat.com>
> ---
> gcc/cp/cp-tree.h | 3 +
> gcc/cp/decl.cc | 41 ++++++----
> gcc/cp/module.cc | 75 +++++++++++++++++++
> gcc/cp/name-lookup.cc | 53 +++++++++++++
> gcc/cp/pt.cc | 32 +++++++-
> .../g++.dg/modules/tpl-friend-10_a.C | 15 ++++
> .../g++.dg/modules/tpl-friend-10_b.C | 5 ++
> .../g++.dg/modules/tpl-friend-10_c.C | 7 ++
> .../g++.dg/modules/tpl-friend-10_d.C | 8 ++
> .../g++.dg/modules/tpl-friend-11_a.C | 14 ++++
> .../g++.dg/modules/tpl-friend-11_b.C | 5 ++
> .../g++.dg/modules/tpl-friend-12_a.C | 10 +++
> .../g++.dg/modules/tpl-friend-12_b.C | 9 +++
> .../g++.dg/modules/tpl-friend-12_c.C | 10 +++
> .../g++.dg/modules/tpl-friend-12_d.C | 8 ++
> .../g++.dg/modules/tpl-friend-12_e.C | 7 ++
> .../g++.dg/modules/tpl-friend-12_f.C | 8 ++
> .../g++.dg/modules/tpl-friend-13_a.C | 13 ++++
> .../g++.dg/modules/tpl-friend-13_b.C | 11 +++
> .../g++.dg/modules/tpl-friend-13_c.C | 13 ++++
> .../g++.dg/modules/tpl-friend-13_d.C | 7 ++
> .../g++.dg/modules/tpl-friend-13_e.C | 18 +++++
> .../g++.dg/modules/tpl-friend-13_f.C | 7 ++
> .../g++.dg/modules/tpl-friend-13_g.C | 11 +++
> .../g++.dg/modules/tpl-friend-14_a.C | 8 ++
> .../g++.dg/modules/tpl-friend-14_b.C | 8 ++
> .../g++.dg/modules/tpl-friend-14_c.C | 7 ++
> .../g++.dg/modules/tpl-friend-14_d.C | 9 +++
> gcc/testsuite/g++.dg/modules/tpl-friend-9.C | 13 ++++
> 29 files changed, 418 insertions(+), 17 deletions(-)
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-10_a.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-10_b.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-10_c.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-10_d.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-11_a.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-11_b.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-12_a.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-12_b.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-12_c.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-12_d.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-12_e.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-12_f.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-13_a.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-13_b.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-13_c.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-13_d.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-13_e.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-13_f.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-13_g.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-14_a.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-14_b.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-14_c.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-14_d.C
> create mode 100644 gcc/testsuite/g++.dg/modules/tpl-friend-9.C
>
> diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
> index 9975dc78456..0c14241fce7 100644
> --- a/gcc/cp/cp-tree.h
> +++ b/gcc/cp/cp-tree.h
> @@ -7417,6 +7417,8 @@ extern unsigned get_importing_module (tree, bool =
> false) ATTRIBUTE_PURE;
> extern void set_instantiating_module (tree);
> extern void set_defining_module (tree);
> extern void maybe_key_decl (tree ctx, tree decl);
> +extern void propagate_defining_module (tree decl, tree orig);
> +extern void remove_defining_module (tree decl);
>
> extern void mangle_module (int m, bool include_partition);
> extern void mangle_module_fini ();
> @@ -7650,6 +7652,7 @@ extern bool template_guide_p
> (const_tree);
> extern bool builtin_guide_p (const_tree);
> extern void store_explicit_specifier (tree, tree);
> extern tree lookup_explicit_specifier (tree);
> +extern tree lookup_imported_hidden_friend (tree);
> extern void walk_specializations (bool,
> void (*)(bool, spec_entry *,
> void *),
> diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
> index 91268ff631d..8fd39957fdc 100644
> --- a/gcc/cp/decl.cc
> +++ b/gcc/cp/decl.cc
> @@ -2276,30 +2276,35 @@ duplicate_decls (tree newdecl, tree olddecl, bool
> hiding, bool was_hidden)
>
> if (modules_p ()
> && TREE_CODE (CP_DECL_CONTEXT (olddecl)) == NAMESPACE_DECL
> - && TREE_CODE (olddecl) != NAMESPACE_DECL
> - && !hiding)
> + && TREE_CODE (olddecl) != NAMESPACE_DECL)
> {
> if (!module_may_redeclare (olddecl, newdecl))
> return error_mark_node;
>
> - tree not_tmpl = STRIP_TEMPLATE (olddecl);
> - if (DECL_LANG_SPECIFIC (not_tmpl)
> - && DECL_MODULE_ATTACH_P (not_tmpl)
> - /* Typedefs are not entities and so are OK to be redeclared
> - as exported: see [module.interface]/p6. */
> - && TREE_CODE (olddecl) != TYPE_DECL)
> + if (!hiding)
> {
> - if (DECL_MODULE_EXPORT_P (STRIP_TEMPLATE (newdecl))
> - && !DECL_MODULE_EXPORT_P (not_tmpl))
> + /* The old declaration should match the exportingness of the new
> + declaration. But hidden friend declarations just keep the
> + exportingness of the old declaration; see CWG2588. */
> + tree not_tmpl = STRIP_TEMPLATE (olddecl);
> + if (DECL_LANG_SPECIFIC (not_tmpl)
> + && DECL_MODULE_ATTACH_P (not_tmpl)
> + /* Typedefs are not entities and so are OK to be redeclared
> + as exported: see [module.interface]/p6. */
> + && TREE_CODE (olddecl) != TYPE_DECL)
> {
> - auto_diagnostic_group d;
> - error ("conflicting exporting for declaration %qD", newdecl);
> - inform (olddecl_loc,
> - "previously declared here without exporting");
> + if (DECL_MODULE_EXPORT_P (newdecl)
> + && !DECL_MODULE_EXPORT_P (not_tmpl))
> + {
> + auto_diagnostic_group d;
> + error ("conflicting exporting for declaration %qD", newdecl);
> + inform (olddecl_loc,
> + "previously declared here without exporting");
> + }
> }
> + else if (DECL_MODULE_EXPORT_P (newdecl))
> + DECL_MODULE_EXPORT_P (not_tmpl) = true;
> }
> - else if (DECL_MODULE_EXPORT_P (newdecl))
> - DECL_MODULE_EXPORT_P (not_tmpl) = true;
> }
>
> /* We have committed to returning OLDDECL at this point. */
> @@ -3321,6 +3326,10 @@ duplicate_decls (tree newdecl, tree olddecl, bool
> hiding, bool was_hidden)
> if (flag_concepts)
> remove_constraints (newdecl);
>
> + /* And similarly for any module tracking data. */
> + if (modules_p ())
> + remove_defining_module (newdecl);
> +
> ggc_free (newdecl);
>
> return olddecl;
> diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc
> index c2f077d6fd8..85c410aaa4c 100644
> --- a/gcc/cp/module.cc
> +++ b/gcc/cp/module.cc
> @@ -2727,6 +2727,12 @@ vec<tree, va_heap, vl_embed> *post_load_decls;
> typedef hash_map<tree, auto_vec<tree>> keyed_map_t;
> static keyed_map_t *keyed_table;
>
> +/* Instantiations of temploid friends imported from another module
> + need to be attached to the same module as the temploid. This maps
> + these decls to the temploid they are instantiated them, as there is
> + no other easy way to get this information. */
> +static GTY((cache)) decl_tree_cache_map *imported_temploid_friends;
> +
> /********************************************************************/
> /* Tree streaming. The tree streaming is very specific to the tree
> structures themselves. A tag indicates the kind of tree being
> @@ -7820,6 +7826,12 @@ trees_out::decl_value (tree decl, depset *dep)
> && DECL_MODULE_ATTACH_P (not_tmpl))
> is_attached = true;
>
> + /* But don't consider imported temploid friends as attached,
> + since importers will need to merge this decl even if it was
> + attached to a different module. */
> + if (imported_temploid_friends->get (decl))
> + is_attached = false;
> +
> bits.b (is_attached);
> }
> bits.b (dep && dep->has_defn ());
> @@ -7997,6 +8009,15 @@ trees_out::decl_value (tree decl, depset *dep)
> }
> }
>
> + if (TREE_CODE (inner) == FUNCTION_DECL
> + || TREE_CODE (inner) == TYPE_DECL)
> + {
> + /* Write imported temploid friends so that importers can reconstruct
> + this information on stream-in. */
> + tree* slot = imported_temploid_friends->get (decl);
> + tree_node (slot ? *slot : NULL_TREE);
> + }
> +
> bool is_typedef = false;
> if (!type && TREE_CODE (inner) == TYPE_DECL)
> {
> @@ -8303,6 +8324,12 @@ trees_in::decl_value ()
> }
> }
>
> + if (TREE_CODE (inner) == FUNCTION_DECL
> + || TREE_CODE (inner) == TYPE_DECL)
> + if (tree owner = tree_node ())
> + if (is_new)
> + imported_temploid_friends->put (decl, owner);
> +
> /* Regular typedefs will have a NULL TREE_TYPE at this point. */
> unsigned tdef_flags = 0;
> bool is_typedef = false;
> @@ -18941,6 +18968,12 @@ get_originating_module_decl (tree decl)
> && DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (decl))
> decl = TYPE_NAME (DECL_CHAIN (decl));
>
> + /* An imported temploid friend is attached to the same module the
> + befriending class was. */
> + if (imported_temploid_friends)
> + if (tree *slot = imported_temploid_friends->get (decl))
> + decl = *slot;
> +
> int use;
> if (tree ti = node_template_info (decl, use))
> {
> @@ -19249,6 +19282,46 @@ maybe_key_decl (tree ctx, tree decl)
> vec.safe_push (decl);
> }
>
> +/* DECL is an instantiated friend that should be attached to the same
> + module that ORIG is. */
> +
> +void
> +propagate_defining_module (tree decl, tree orig)
> +{
> + if (!modules_p ())
> + return;
> +
> + tree not_tmpl = STRIP_TEMPLATE (orig);
> + if (DECL_LANG_SPECIFIC (not_tmpl) && DECL_MODULE_ATTACH_P (not_tmpl))
> + {
> + tree inner = STRIP_TEMPLATE (decl);
> + retrofit_lang_decl (inner);
> + DECL_MODULE_ATTACH_P (inner) = true;
> + }
> +
> + if (DECL_LANG_SPECIFIC (not_tmpl) && DECL_MODULE_IMPORT_P (not_tmpl))
> + {
> + bool exists = imported_temploid_friends->put (decl, orig);
> +
> + /* We should only be called if lookup for an existing decl
> + failed, in which case there shouldn't already be an entry
> + in the map. */
> + gcc_assert (!exists);
> + }
> +}
> +
> +/* DECL is being freed, clear data we don't need anymore. */
> +
> +void
> +remove_defining_module (tree decl)
> +{
> + if (!modules_p ())
> + return;
> +
> + if (imported_temploid_friends)
> + imported_temploid_friends->remove (decl);
> +}
> +
> /* Create the flat name string. It is simplest to have it handy. */
>
> void
> @@ -20462,6 +20535,8 @@ init_modules (cpp_reader *reader)
> pending_table = new pending_map_t (EXPERIMENT (1, 400));
> entity_map = new entity_map_t (EXPERIMENT (1, 400));
> vec_safe_reserve (entity_ary, EXPERIMENT (1, 400));
> + imported_temploid_friends
> + = decl_tree_cache_map::create_ggc (EXPERIMENT (1, 400));
> }
>
> #if CHECKING_P
> diff --git a/gcc/cp/name-lookup.cc b/gcc/cp/name-lookup.cc
> index 7af7f00e34c..4dffc0e9acc 100644
> --- a/gcc/cp/name-lookup.cc
> +++ b/gcc/cp/name-lookup.cc
> @@ -4131,6 +4131,22 @@ mergeable_namespace_slots (tree ns, tree name, bool
> is_attached, tree *vec)
> return vslot;
> }
>
> +/* Retrieve the bindings for an existing mergeable entity in namespace
> + NS slot NAME. Returns NULL if no such bindings exists. */
> +
> +static tree
> +get_mergeable_namespace_binding (tree ns, tree name, bool is_attached)
> +{
> + tree *mslot = find_namespace_slot (ns, name, false);
> + if (!mslot || !*mslot || TREE_CODE (*mslot) != BINDING_VECTOR)
> + return NULL_TREE;
> +
> + tree *vslot = get_fixed_binding_slot
> + (mslot, name, is_attached ? BINDING_SLOT_PARTITION : BINDING_SLOT_GLOBAL,
> + false);
> + return vslot ? *vslot : NULL_TREE;
> +}
> +
> /* DECL is a new mergeable namespace-scope decl. Add it to the
> mergeable entities on GSLOT. */
>
> @@ -4453,6 +4469,43 @@ push_local_binding (tree id, tree decl, bool is_using)
> add_decl_to_level (b, decl);
> }
>
> +/* Lookup the FRIEND_TMPL within all merged module imports. Used to dedup
> + instantiations of temploid hidden friends from imported modules. */
> +
> +tree
> +lookup_imported_hidden_friend (tree friend_tmpl)
> +{
> + /* For a class-scope friend class it should have been found by regular
> + name lookup. Otherwise we're looking in the current namespace. */
> + gcc_checking_assert (CP_DECL_CONTEXT (friend_tmpl) == current_namespace);
> +
> + tree inner = DECL_TEMPLATE_RESULT (friend_tmpl);
> + if (!DECL_LANG_SPECIFIC (inner)
> + || !DECL_MODULE_IMPORT_P (inner))
> + return NULL_TREE;
> +
> + /* Imported temploid friends are not considered as attached to this
> + module for merging purposes. */
> + tree bind = get_mergeable_namespace_binding (current_namespace,
> + DECL_NAME (inner), false);
> + 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);
> + 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)
> + return *iter;
> +
> + return NULL_TREE;
> +}
> +
>
> /* true means unconditionally make a BLOCK for the next level pushed. */
>
> diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
> index 3b2106dd3f6..ac7669a7ffb 100644
> --- a/gcc/cp/pt.cc
> +++ b/gcc/cp/pt.cc
> @@ -11512,6 +11512,10 @@ tsubst_friend_function (tree decl, tree args)
> new_friend_result_template_info = DECL_TEMPLATE_INFO (not_tmpl);
> }
>
> + /* We need to propagate module attachment for the new friend from the
> + owner of this template. */
> + propagate_defining_module (new_friend, decl);
> +
> /* Inside pushdecl_namespace_level, we will push into the
> current namespace. However, the friend function should go
> into the namespace of the template. */
> @@ -11715,6 +11719,12 @@ tsubst_friend_class (tree friend_tmpl, tree args)
> tmpl = lookup_name (DECL_NAME (friend_tmpl), LOOK_where::CLASS_NAMESPACE,
> LOOK_want::NORMAL | LOOK_want::HIDDEN_FRIEND);
>
> + if (!tmpl)
> + /* If we didn't find by name lookup, the type may still exist but as a
> + 'hidden' import; we should check for this too to avoid accidentally
> + instantiating a duplicate. */
> + tmpl = lookup_imported_hidden_friend (friend_tmpl);
> +
> if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
> {
> /* The friend template has already been declared. Just
> @@ -11723,6 +11733,12 @@ tsubst_friend_class (tree friend_tmpl, tree args)
> of course. We only need the innermost template parameters
> because that is all that redeclare_class_template will look
> at. */
> +
> + if (modules_p ())
> + /* Check that the existing declaration's module attachment is
> + compatible with the attachment of the friend template. */
> + module_may_redeclare (tmpl, friend_tmpl);
> +
> if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
> > TMPL_ARGS_DEPTH (args))
> {
> @@ -11751,9 +11767,19 @@ tsubst_friend_class (tree friend_tmpl, tree args)
> if (tmpl != error_mark_node)
> {
> /* The new TMPL is not an instantiation of anything, so we
> - forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE
> + forget its origins. It is also not a specialization of
> + anything. We don't reset CLASSTYPE_TI_TEMPLATE
> for the new type because that is supposed to be the
> corresponding template decl, i.e., TMPL. */
> + if (modules_p ())
> + {
> + spec_entry elt;
> + elt.tmpl = friend_tmpl;
> + elt.args = CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl));
> + elt.spec = TREE_TYPE (tmpl);
> + type_specializations->remove_elt (&elt);
> + }
> +
> DECL_USE_TEMPLATE (tmpl) = 0;
> DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
> CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
> @@ -11772,6 +11798,10 @@ tsubst_friend_class (tree friend_tmpl, tree args)
> args, tf_warning_or_error);
> }
>
> + /* We need to propagate the attachment of the original template to the
> + newly instantiated template type. */
> + propagate_defining_module (tmpl, friend_tmpl);
> +
> /* Inject this template into the enclosing namspace scope. */
> tmpl = pushdecl_namespace_level (tmpl, /*hiding=*/true);
> }
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-10_a.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-10_a.C
> new file mode 100644
> index 00000000000..7547326e554
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-10_a.C
> @@ -0,0 +1,15 @@
> +// PR c++/105320
> +// { dg-additional-options "-fmodules-ts -Wno-global-module" }
> +// { dg-module-cmi test_support }
> +
> +module;
> +template<class> struct _Sp_atomic;
> +template<class> struct shared_ptr {
> + template<class> friend struct _Sp_atomic;
> + using atomic_type = _Sp_atomic<int>;
> +};
> +export module test_support;
> +export
> +template<class T> struct A {
> + shared_ptr<T> data;
> +};
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-10_b.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-10_b.C
> new file mode 100644
> index 00000000000..6b88ee4258b
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-10_b.C
> @@ -0,0 +1,5 @@
> +// PR c++/105320
> +// { dg-additional-options "-fmodules-ts" }
> +
> +import test_support;
> +A<int> a;
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-10_c.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-10_c.C
> new file mode 100644
> index 00000000000..90bcd18a45e
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-10_c.C
> @@ -0,0 +1,7 @@
> +// PR c++/105320
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi user:part }
> +
> +export module user:part;
> +import test_support;
> +export A<int> b;
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-10_d.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-10_d.C
> new file mode 100644
> index 00000000000..861d19c9eaa
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-10_d.C
> @@ -0,0 +1,8 @@
> +// PR c++/105320
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi user }
> +
> +export module user;
> +export import :part;
> +import test_support;
> +A<double> c;
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-11_a.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-11_a.C
> new file mode 100644
> index 00000000000..f29eebd1a7f
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-11_a.C
> @@ -0,0 +1,14 @@
> +// PR c++/114275
> +// { dg-additional-options "-fmodules-ts -Wno-global-module" }
> +// { dg-module-cmi M }
> +
> +module;
> +
> +template <typename... _Elements> struct T;
> +
> +template <typename H> struct T<H> {
> + template <typename...> friend struct T;
> +};
> +
> +export module M;
> +export template <typename=void> void fun() { T<int> t; }
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-11_b.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-11_b.C
> new file mode 100644
> index 00000000000..5bf79998139
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-11_b.C
> @@ -0,0 +1,5 @@
> +// PR c++/114275
> +// { dg-additional-options "-fmodules-ts" }
> +
> +import M;
> +int main() { fun(); }
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-12_a.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-12_a.C
> new file mode 100644
> index 00000000000..216dbf62c71
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-12_a.C
> @@ -0,0 +1,10 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi M:A }
> +
> +module M:A;
> +
> +template <typename T> struct A {
> + template <typename U> friend struct B;
> +private:
> + int x = 42;
> +};
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-12_b.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-12_b.C
> new file mode 100644
> index 00000000000..26e1c38b518
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-12_b.C
> @@ -0,0 +1,9 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi M:B }
> +
> +export module M:B;
> +import :A;
> +
> +export template <typename U> struct B {
> + int foo(A<U> a) { return a.x; }
> +};
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-12_c.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-12_c.C
> new file mode 100644
> index 00000000000..e44c2819cfd
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-12_c.C
> @@ -0,0 +1,10 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi M:C }
> +
> +export module M:C;
> +import :A;
> +
> +template <typename T> struct B;
> +export template <typename T, typename U> int bar(B<T> t, U u) {
> + return t.foo(u);
> +}
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-12_d.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-12_d.C
> new file mode 100644
> index 00000000000..9a575ad5046
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-12_d.C
> @@ -0,0 +1,8 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi M }
> +
> +export module M;
> +export import :B;
> +export import :C;
> +
> +export int go_in_module();
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-12_e.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-12_e.C
> new file mode 100644
> index 00000000000..329d1e8b263
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-12_e.C
> @@ -0,0 +1,7 @@
> +// { dg-additional-options "-fmodules-ts" }
> +
> +module M;
> +
> +int go_in_module() {
> + return bar(B<int>{}, A<int>{});
> +}
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-12_f.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-12_f.C
> new file mode 100644
> index 00000000000..c9855663fbd
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-12_f.C
> @@ -0,0 +1,8 @@
> +// { dg-additional-options "-fmodules-ts" }
> +
> +import M;
> +
> +int main() {
> + B<double> b{};
> + go_in_module();
> +}
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-13_a.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-13_a.C
> new file mode 100644
> index 00000000000..8c972776d60
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-13_a.C
> @@ -0,0 +1,13 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi M }
> +
> +export module M;
> +export template <typename> struct A {
> + friend struct S;
> + template <typename> friend struct T;
> +};
> +
> +export template <typename> struct B {
> + friend void f();
> + template <typename> friend void g();
> +};
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-13_b.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-13_b.C
> new file mode 100644
> index 00000000000..0e27e97b113
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-13_b.C
> @@ -0,0 +1,11 @@
> +// { dg-additional-options "-fmodules-ts" }
> +
> +import M;
> +
> +A<int> a;
> +struct S {}; // { dg-error "conflicts with import" }
> +template <typename> struct T {}; // { dg-error "conflicts with import" }
> +
> +B<int> c;
> +void f() {} // { dg-error "conflicts with import" }
> +template <typename> void g() {} // { dg-error "conflicts with import" }
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-13_c.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-13_c.C
> new file mode 100644
> index 00000000000..3464aa26bf8
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-13_c.C
> @@ -0,0 +1,13 @@
> +// { dg-additional-options "-fmodules-ts" }
> +
> +import M;
> +
> +struct S {}; // { dg-error "conflicts with import" }
> +template <typename> struct T {}; // { dg-message "previously declared" }
> +A<int> a; // { dg-message "required from here" }
> +
> +void f() {} // { dg-message "previously declared" }
> +template <typename> void g() {} // { dg-message "previously declared" }
> +B<int> b; // { dg-message "required from here" }
> +
> +// { dg-error "conflicting declaration" "" { target *-*-* } 0 }
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-13_d.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-13_d.C
> new file mode 100644
> index 00000000000..5b935474ab2
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-13_d.C
> @@ -0,0 +1,7 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi X }
> +
> +export module X;
> +export import M;
> +A<int> ax;
> +B<int> bx;
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-13_e.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-13_e.C
> new file mode 100644
> index 00000000000..afbd0a39c23
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-13_e.C
> @@ -0,0 +1,18 @@
> +// { dg-additional-options "-fmodules-ts" }
> +
> +// 'import X' does not correctly notice that S has already been declared.
> +struct S {}; // { dg-message "previously declared" "" { xfail *-*-* } }
> +template <typename> struct T {}; // { dg-message "previously declared" }
> +void f() {} // { dg-message "previously declared" }
> +template <typename T> void g() {} // { dg-message "previously declared" }
> +
> +import X;
> +A<double> a2; // { dg-message "required from here" }
> +B<double> b2; // { dg-message "required from here" }
> +
> +// specifically, S and T are defined in M, not X, despite the instantiation
> being in X
> +// { dg-error "conflicting declaration \[^\n\r\]* S@M" "" { xfail *-*-* } 0 }
> +// { dg-error "conflicting declaration \[^\n\r\]* T@M" "" { target *-*-* } 0
> }
> +// and similarly for f and g
> +// { dg-error "conflicting declaration \[^\n\r\]* f@M" "" { target *-*-* } 0
> }
> +// { dg-error "conflicting declaration \[^\n\r\]* g@M" "" { target *-*-* } 0
> }
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-13_f.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-13_f.C
> new file mode 100644
> index 00000000000..287f95c7bdc
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-13_f.C
> @@ -0,0 +1,7 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi Y }
> +
> +export module Y;
> +export import M;
> +A<double> ay;
> +B<double> by;
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-13_g.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-13_g.C
> new file mode 100644
> index 00000000000..b7da60f2322
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-13_g.C
> @@ -0,0 +1,11 @@
> +// { dg-additional-options "-fmodules-ts" }
> +
> +import X;
> +import Y;
> +
> +// This should happily refer to the same S and T
> +// as already instantiated in both X and Y
> +A<long> az;
> +
> +// And same for f and g
> +B<long> bz;
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-14_a.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-14_a.C
> new file mode 100644
> index 00000000000..6912512ecf7
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-14_a.C
> @@ -0,0 +1,8 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi M }
> +
> +export module M;
> +
> +export extern "C++" template <typename> struct A {
> + template <typename> friend struct B;
> +};
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-14_b.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-14_b.C
> new file mode 100644
> index 00000000000..5f8aa7fd62e
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-14_b.C
> @@ -0,0 +1,8 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi X }
> +
> +export module X;
> +export import M;
> +
> +A<int> x;
> +export extern "C++" template <typename T> struct B { using type = T; };
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-14_c.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-14_c.C
> new file mode 100644
> index 00000000000..8d89298878a
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-14_c.C
> @@ -0,0 +1,7 @@
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi Y }
> +
> +export module Y;
> +export import M;
> +
> +A<double> x;
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-14_d.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-14_d.C
> new file mode 100644
> index 00000000000..7a842586b62
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-14_d.C
> @@ -0,0 +1,9 @@
> +// { dg-additional-options "-fmodules-ts" }
> +
> +import X;
> +import Y;
> +
> +int main() {
> + A<long> a;
> + B<int>::type r = 10;
> +}
> diff --git a/gcc/testsuite/g++.dg/modules/tpl-friend-9.C
> b/gcc/testsuite/g++.dg/modules/tpl-friend-9.C
> new file mode 100644
> index 00000000000..c7216f0f8c1
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/tpl-friend-9.C
> @@ -0,0 +1,13 @@
> +// PR c++/114275
> +// { dg-additional-options "-fmodules-ts" }
> +// { dg-module-cmi M }
> +
> +export module M;
> +
> +template<class> struct A {
> + template<class> friend struct B;
> + friend void C();
> +};
> +A<int> a;
> +void C() {}
> +template<class> struct B { };
> --
> 2.43.2
>
>
