The goal is to correctly identify diagnostics that are emitted by virtue
of -Wformat-signedness.
Before this change, diagnostic messages triggered by -Wformat-signedness
might look like:
format specifies type 'unsigned int' but the argument has type 'int'
[-Wformat]
signedness of format specifier 'u' is incompatible with 'c' [-Wformat]
With this change:
format specifies type 'unsigned int' but the argument has type 'int',
which differs in signedness [-Wformat-signedness]
signedness of format specifier 'u' is incompatible with 'c'
[-Wformat-signedness]
Fix:
- handleFormatSignedness can now return NoMatchSignedness. Callers
handle this.
- warn_format_conversion_argument_type extends the message it used to
emit by a string that
mentions "signedness".
- warn_format_cmp_specifier_sign_mismatch is now correctly categorized
as a
diagnostic controlled by -Wformat-signedness.