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

[kadir çetinkaya 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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kadircet wrote:

As you well know these discrepancies are coming from https://github.com/llvm/llvm-project/blob/main/clang/include/clang/Basic/LLVM.h. It's really hard to know/remember what's available there and what isn't. Moreover the header only forward-declares, so at usage side one actually needs to include the actual header from `llvm/...`.

Hence can't do this for `SpecialCaseList` but doing it for others that I can. But I think in the long run it'd be interesting to see if people still find this intermediate header useful or not.

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