https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92150
--- Comment #2 from Jason Merrill <jason at gcc dot gnu.org> --- Author: jason Date: Fri Dec 13 05:09:57 2019 New Revision: 279332 URL: https://gcc.gnu.org/viewcvs?rev=279332&root=gcc&view=rev Log: PR c++/92150 - partial specialization with class NTTP. Here unify was getting confused by the VIEW_CONVERT_EXPR we add in finish_id_expression_1 to make class NTTP const when they're used in an expression. Tested x86_64-pc-linux-gnu, applying to trunk. * pt.c (unify): Handle VIEW_CONVERT_EXPR. Added: branches/gcc-9-branch/gcc/testsuite/g++.dg/cpp2a/nontype-class24.C Modified: branches/gcc-9-branch/gcc/cp/ChangeLog branches/gcc-9-branch/gcc/cp/pt.c