[clang-tools-extra] [clang] [libc] [flang] [llvm] Fix clang to recognize new C23 modifiers %w and %wf when printing (PR #71771)

[Aaron Ballman via cfe-commits]

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@@ -417,6 +419,7 @@ class FormatSpecifier {
   ///  http://www.opengroup.org/onlinepubs/009695399/functions/printf.html
   bool UsesPositionalArg;
   unsigned argIndex;
+  unsigned size;
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AaronBallman wrote:

I think it might be more clear to call this `ExplicitlyFixedSize` or something along those lines.

https://github.com/llvm/llvm-project/pull/71771