https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98770
--- Comment #1 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:af66f4f1b06f5e0c099dfced2fcf7b1b23fa53e7 commit r11-6954-gaf66f4f1b06f5e0c099dfced2fcf7b1b23fa53e7 Author: Nathan Sidwell <nat...@acm.org> Date: Thu Jan 28 04:48:33 2021 -0800 c++: header unit template alias merging [PR 98770] Typedefs are streamed by streaming the underlying type, and then recreating the typedef. But this breaks checking a duplicate is the same as the original when it is a template alias -- we end up checking a template alias (eg __void_t) against the underlying type (void). And those are not the same template alias. This stops pretendig that the underlying type is the typedef for that checking and tells is_matching_decl 'you have a typedef', so it knows what to do. (We do not want to recreate the typedef of the duplicate, because that whole set of nodes is going to go away.) PR c++/98770 gcc/cp/ * module.cc (trees_out::decl_value): Swap is_typedef & TYPE_NAME check order. (trees_in::decl_value): Do typedef frobbing only when installing a new typedef, adjust is_matching_decl call. Swap is_typedef & TYPE_NAME check. (trees_in::is_matching_decl): Add is_typedef parm. Adjust variable names and deal with typedef checking. gcc/testsuite/ * g++.dg/modules/pr98770_a.C: New. * g++.dg/modules/pr98770_b.C: New.
