[PATCH] D72242: Fix crash on value dependent bitfields in if conditions in templates

[Richard Smith - zygoloid via Phabricator via cfe-commits]

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This is not an appropriate fix; the code is locally correct. The right way to handle this is exactly what Clang currently does: if the expression is not type-dependent, then contextually convert to `bool`, and if it's not value-dependent, then make sure it's a constant expression.

The bug is that we should treat the name of a bit-field with a value-dependent width as being type-dependent -- the `c` expression in the testcase should be a type-dependent expression (even though its type is known to be `int`) because we don't know how to promote it due to the value-dependent bit-width. (This is ultimately a bug in the C++ standard, which fails to provide such a rule, but I've reported that to the committee and it should be fixed in the standard at some point. But the right fix seems obvious enough that we can just do it.)


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  https://reviews.llvm.org/D72242/new/

https://reviews.llvm.org/D72242