https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114947
--- Comment #1 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Nathaniel Shead <nsh...@gcc.gnu.org>: https://gcc.gnu.org/g:7fa0ffa4f789683ba80e93cd10546cb7bd2c3d8a commit r15-810-g7fa0ffa4f789683ba80e93cd10546cb7bd2c3d8a Author: Nathaniel Shead <nathanielosh...@gmail.com> Date: Sun May 12 22:31:01 2024 +1000 c++/modules: Ensure all partial specialisations are tracked [PR114947] Constrained partial specialisations aren't all necessarily tracked on the instantiation table. The modules code uses a separate 'partial_specializations' table to track them instead to ensure that they get walked and emitted when emitting a module, but currently this does not always happen. The attached testcase fails in two ways. First, because the partial specialisation is just a declaration (and not a definition), 'set_defining_module' never ends up getting called on it and so it never gets added to the partial specialisation table. We fix this by ensuring that when partial specializations are created they always get added, and so we never miss one. To prevent adding partial specialisations multiple times we split this out as a new function. The second way it fails is that when exporting the primary interface for a module with partitions, we also re-walk the specializations of all imported partitions to merge them into a single BMI. So this patch ensures that after calling 'match_mergeable_specialization' we also ensure that if the name came from a partition it gets added to the specialization table so that a dependency is correctly created for it. PR c++/114947 gcc/cp/ChangeLog: * cp-tree.h (set_defining_module_for_partial_spec): Declare. * module.cc (trees_in::decl_value): Track partial specs coming from partitions. (set_defining_module): Don't track partial specialisations here anymore. (set_defining_module_for_partial_spec): New function. * pt.cc (process_partial_specialization): Call it. gcc/testsuite/ChangeLog: * g++.dg/modules/partial-4_a.C: New test. * g++.dg/modules/partial-4_b.C: New test. Signed-off-by: Nathaniel Shead <nathanielosh...@gmail.com>
