https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90099
--- Comment #1 from Jason Merrill <jason at gcc dot gnu.org> --- Author: jason Date: Fri Jul 19 06:52:47 2019 New Revision: 273591 URL: https://gcc.gnu.org/viewcvs?rev=273591&root=gcc&view=rev Log: PR c++/90098 - partial specialization and class non-type parms. A non-type template parameter of class type used in an expression has const-qualified type; the pt.c hunks deal with this difference from the unqualified type of the parameter declaration. WAhen we use such a parameter as an argument to another template, we don't want to confuse things by copying it, we should pass it straight through. And we might as well skip copying other classes in constant evaluation context in a template, too; we'll get the copy semantics at instantiation time. PR c++/90099 PR c++/90101 * call.c (build_converted_constant_expr_internal): Don't copy. * pt.c (process_partial_specialization): Allow VIEW_CONVERT_EXPR around class non-type parameter. (unify) [TEMPLATE_PARM_INDEX]: Ignore cv-quals. Added: trunk/gcc/testsuite/g++.dg/cpp2a/nontype-class18.C trunk/gcc/testsuite/g++.dg/cpp2a/nontype-class19.C trunk/gcc/testsuite/g++.dg/cpp2a/nontype-class20.C Modified: trunk/gcc/cp/ChangeLog trunk/gcc/cp/call.c trunk/gcc/cp/pt.c
