[PATCH] D71142: [Sema] Validate large bitfields

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

rsmith added a comment.

It seems fine and reasonable to reject this as a violation of an implementation limit. Can we actually support the full range 2^64 bits range, or would it be wiser to pick a smaller limit? (There's at least no point in allowing bit-widths that would mean the size of the bitfield doesn't fit in `size_t`, which means no more than 35 bits for a 32-bit target.)



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Comment at: clang/include/clang/Basic/DiagnosticSemaKinds.td:5186-5189
+def warn_bitfield_width_exceeds_maximum_width: Error<
+  "width of bit-field %0 doesn't fit in a 64 bit unsigned integer">;
+def warn_anon_bitfield_width_exceeds_maximum_width : Error<
+  "width of anonymous bit-field doesn't fit in a 64 bit unsigned integer">;
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aaron.ballman wrote:
> I feel like this situation should be an error rather than a warning -- what could the code possibly have meant?
The name of the diagnostic and the kind of diagnostic should agree. Currently we have `warn_` vs `Error<`.


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https://reviews.llvm.org/D71142