[Bug c++/108975] [10/11/12/13 Regression] ICE on constexpr variable used as nontype template since r9-5473-ge32fc4499f863f

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108975

--- Comment #13 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Jason Merrill <jason@gcc.gnu.org>:

https://gcc.gnu.org/g:6f90de97634d6f1617a054429f28b85fbfbd8b6f

commit r13-6743-g6f90de97634d6f1617a054429f28b85fbfbd8b6f
Author: Jason Merrill <jason@redhat.com>
Date:   Fri Mar 17 17:26:40 2023 -0400

    c++: constant, array, lambda, template [PR108975]

    When a lambda refers to a constant local variable in the enclosing scope,
we
    tentatively capture it, but if we end up pulling out its constant value, we
    go back at the end of the lambda and prune any unneeded captures.  Here
    while parsing the template we decided that the dim capture was unneeded,
    because we folded it away, but then we brought back the use in the template
    trees that try to preserve the source representation with added type info.
    So then when we tried to instantiate that use, we couldn't find what it was
    trying to use, and crashed.

    Fixed by not trying to prune when parsing a template; we'll prune at
    instantiation time.

            PR c++/108975

    gcc/cp/ChangeLog:

            * lambda.cc (prune_lambda_captures): Don't bother in a template.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp0x/lambda/lambda-const11.C: New test.