[Bug c++/67685] ICE on invalid requires expression

[andrew.n.sutton at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67685

Andrew Sutton <andrew.n.sutton at gmail dot com> changed:

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                 CC|                            |andrew.n.sutton at gmail dot com

--- Comment #2 from Andrew Sutton <andrew.n.sutton at gmail dot com> ---
Quickly investigating. In tsubst_requires_expr, we add to the local
specialization stack, which means that any local variables or parameters
referenced within the requires-expression will not be visible, which ultimately
causes undefined behavior in tsubst_copy.