[clang] [Sema] Suggest missing format attributes (PR #166738)

[Vladimir Vuksanovic via cfe-commits]

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@@ -401,6 +401,8 @@ Improvements to Clang's diagnostics
   or continue (#GH166013)
 - Clang now emits a diagnostic in case `vector_size` or `ext_vector_type`
   attributes are used with a negative size (#GH165463).
+- Clang now detects potential missing format attributes on function declarations
+  when calling format functions. (#GH60718)
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vvuksanovic wrote:

That issue was closed by #70024, but it was later reverted. Then #105479 was created to fix the issues, but never merged.

This is an updated version of #105479 with most comments addressed.

https://github.com/llvm/llvm-project/pull/166738