[clang] [clang-tools-extra] [llvm] [clang] Introduce diagnostics suppression mappings (PR #112517)

[Aaron Ballman via cfe-commits]

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@@ -477,6 +486,136 @@ void DiagnosticsEngine::setSeverityForAll(diag::Flavor Flavor,
       setSeverity(Diag, Map, Loc);
 }
 
+namespace {
+// FIXME: We should isolate the parser from SpecialCaseList and just use it
+// here.
+class WarningsSpecialCaseList : public llvm::SpecialCaseList {
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AaronBallman wrote:

Prevailing style in this file also drops the `llvm::` prefixes. Probably worth taking a pass over the whole PR to verify you're following the local styles.

https://github.com/llvm/llvm-project/pull/112517