[Bug c++/104594] narrowing of -1 to unsigned char not detected with requires concepts

[ppalka at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104594

--- Comment #4 from Patrick Palka <ppalka at gcc dot gnu.org> ---
N.B. coerce_template_parms sometimes does encode the implicit conversion for a
dependent NTTP argument, but only for sake of specialization matching (in light
of 'auto' template parms IIUC), the IMPLICIT_CONV_EXPR built is a no-op
otherwise.