> Here, when substituting still-dependent args into an alias template, we see
> a non-const type because the default argument is non-const, and is not a
> template parm object because it's still dependent.
>
> Tested x86_64-pc-linux-gnu, applying to trunk.
>
> gcc/cp/ChangeLog:
>
> PR c++/98810
> * pt.c (tsubst_copy) [VIEW_CONVERT_EXPR]: Add const
> to a class non-type template argument that needs it.
>
> gcc/testsuite/ChangeLog:
>
> PR c++/98810
> * g++.dg/cpp2a/nontype-class-defarg1.C: New test.
This apparently went down to the 9 branch as well and introduced:
Running /home/eric/cvs/gcc-9/gcc/testsuite/g++.dg/dg.exp ...
ERROR: g++.dg/cpp2a/nontype-class-defarg1.C -std=c++98: syntax error in
target selector "target c++20" for " dg-do 2 compile { target c++20 } "
ERROR: g++.dg/cpp2a/nontype-class-defarg1.C -std=c++98: syntax error in
target selector "target c++20" for " dg-do 2 compile { target c++20 } "
ERROR: g++.dg/cpp2a/nontype-class-defarg1.C -std=c++14: syntax error in
target selector "target c++20" for " dg-do 2 compile { target c++20 } "
ERROR: g++.dg/cpp2a/nontype-class-defarg1.C -std=c++14: syntax error in
target selector "target c++20" for " dg-do 2 compile { target c++20 } "
ERROR: g++.dg/cpp2a/nontype-class-defarg1.C -std=c++17: syntax error in
target selector "target c++20" for " dg-do 2 compile { target c++20 } "
ERROR: g++.dg/cpp2a/nontype-class-defarg1.C -std=c++17: syntax error in
target selector "target c++20" for " dg-do 2 compile { target c++20 } "
On the contrary, the 10 branch is a in good shape.
--
Eric Botcazou
