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

[via cfe-commits]

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@@ -7093,9 +7105,143 @@ bool Sema::CheckFormatString(const FormatMatchesAttr *Format,
   return false;
 }
 
+static bool CheckMissingFormatAttribute(
+    Sema *S, ArrayRef<const Expr *> Args, Sema::FormatArgumentPassingKind APK,
+    StringLiteral *ReferenceFormatString, unsigned FormatIdx,
+    unsigned FirstDataArg, FormatStringType FormatType, unsigned CallerParamIdx,
+    SourceLocation Loc) {
+  if (S->getDiagnostics().isIgnored(diag::warn_missing_format_attribute,
+                                    SourceLocation()))
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apple-fcloutier wrote:

This needs to use an appropriate source location, or else the check will pass if the diagnostic is enabled on the command line but disabled by a `#pragma gcc diagnostic ignored` region. Isn't `Loc` the source location of the call?

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