[clang] [Clang] Consider preferred_type in bitfield warnings (#116760) (PR #116785)

[Erich Keane via cfe-commits]

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@@ -6404,20 +6404,23 @@ def warn_bitfield_width_exceeds_type_width: Warning<
 def err_bitfield_too_wide : Error<
   "%select{bit-field %1|anonymous bit-field}0 is too wide (%2 bits)">;
 def warn_bitfield_too_small_for_enum : Warning<
-  "bit-field %0 is not wide enough to store all enumerators of %1">,
+  "bit-field %0 is not wide enough to store all enumerators of %select{|preferred type }1%2">,
   InGroup<BitFieldEnumConversion>, DefaultIgnore;
 def note_widen_bitfield : Note<
   "widen this field to %0 bits to store all values of %1">;
 def warn_unsigned_bitfield_assigned_signed_enum : Warning<
-  "assigning value of signed enum type %1 to unsigned bit-field %0; "
+  "assigning value of %select{|preferred }1signed enum type %2 to unsigned bit-field %0; "
   "negative enumerators of enum %1 will be converted to positive values">,
   InGroup<BitFieldEnumConversion>, DefaultIgnore;
 def warn_signed_bitfield_enum_conversion : Warning<
   "signed bit-field %0 needs an extra bit to represent the largest positive "
-  "enumerators of %1">,
+  "enumerators of %select{|preferred type }1%2">,
   InGroup<BitFieldEnumConversion>, DefaultIgnore;
----------------
erichkeane wrote:

I agree, `preferred_type` I think is an opt-into this diagnostic, so splitting it so it isn't default-ignore is a great idea.

https://github.com/llvm/llvm-project/pull/116785