In the standard, constraint satisfaction checking is done on the
normalized form of a constraint.
Clang instead substitutes on the non-normalized form, which causes us to
report substitution failures in template arguments or concept ids, which
is non-conforming but unavoidable without a parameter mapping
This patch normalizes before satisfaction checking. However, we preserve
concept-id nodes in the normalized form, solely for diagnostics
purposes.
This addresses #61811 and related concepts conformance bugs, ideally to
make the remaining implementation of concept template parameters easier
Fixes#135190
Fixes #61811
Co-authored-by: Younan Zhang <zyn7109@gmail.com>
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