https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99283
--- Comment #10 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Nathan Sidwell <nat...@gcc.gnu.org>: https://gcc.gnu.org/g:d82797420c2238e31a7a25fe6db6bd05cd37224d commit r11-7866-gd82797420c2238e31a7a25fe6db6bd05cd37224d Author: Nathan Sidwell <nat...@acm.org> Date: Fri Mar 26 10:46:31 2021 -0700 c++: imported templates and alias-template changes [PR 99283] During development of modules, I had difficulty deciding whether the module flags of a template should live on the decl_template_result, the template_decl, or both. I chose the latter, and require them to be consistent. This and a few other defects show how hard that consistency is. Hence this patch move to holding the flags on the template-decl-result decl. That's the entity various bits of the parser have at the appropriate time. Once needs STRIP_TEMPLATE in a bunch of places, which this patch adds. Also a check that we never give a TEMPLATE_DECL to the module flag accessors. This left a problem with how I was handling template aliases. These were in two parts -- separating the TEMPLATE_DECL from the TYPE_DECL. That seemed somewhat funky, but development showed it necessary. Of course, that causes problems if the TEMPLATE_DECL cannot contain 'am imported' information. Investigating now shows that we do not need to treat them separately. By reverting a bit of template instantiation machinery that caused the problem, we're back on course. I think what has happened is that between then and now, other typedef fixes have corrected the underlying problem this separation was working around. It allows a bunch of cleanup in the decl streamer, as we no longer have to handle a null TEMPLATE_DECL_RESULT. PR c++/99283 gcc/cp/ * cp-tree.h (DECL_MODULE_CHECK): Ban TEMPLATE_DECL. (SET_TYPE_TEMPLATE_INFO): Restore Alias template setting. * decl.c (duplicate_decls): Remove template_decl module flag propagation. * module.cc (merge_kind_name): Add alias tmpl spec as a thing. (dumper::impl::nested_name): Adjust for template-decl module flag change. (trees_in::assert_definition): Likewise. (trees_in::install_entity): Likewise. (trees_out::decl_value): Likewise. Remove alias template separation of template and type_decl. (trees_in::decl_value): Likewise. (trees_out::key_mergeable): Likewise, (trees_in::key_mergeable): Likewise. (trees_out::decl_node): Adjust for template-decl module flag change. (depset::hash::make_dependency): Likewise. (get_originating_module, module_may_redeclare): Likewise. (set_instantiating_module, set_defining_module): Likewise. * name-lookup.c (name_lookup::search_adl): Likewise. (do_pushdecl): Likewise. * pt.c (build_template_decl): Likewise. (lookup_template_class_1): Remove special alias_template handling of DECL_TI_TEMPLATE. (tsubst_template_decl): Likewise. gcc/testsuite/ * g++.dg/modules/pr99283-2_a.H: New. * g++.dg/modules/pr99283-2_b.H: New. * g++.dg/modules/pr99283-2_c.H: New. * g++.dg/modules/pr99283-3_a.H: New. * g++.dg/modules/pr99283-3_b.H: New. * g++.dg/modules/pr99283-4.H: New. * g++.dg/modules/tpl-alias-1_a.H: Adjust scans. * g++.dg/modules/tpl-alias-1_b.C: Adjust scans.