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

[Boaz Brickner via cfe-commits]

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@@ -477,6 +485,100 @@ void DiagnosticsEngine::setSeverityForAll(diag::Flavor Flavor,
       setSeverity(Diag, Map, Loc);
 }
 
+namespace {
+class WarningsSpecialCaseList : public llvm::SpecialCaseList {
+public:
+  static std::unique_ptr<WarningsSpecialCaseList>
+  create(const llvm::MemoryBuffer &MB, std::string &Err) {
+    auto SCL = std::make_unique<WarningsSpecialCaseList>();
+    if (SCL->createInternal(&MB, Err))
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bricknerb wrote:

Consider reversing the condition to return nullptr early in case you want to do more processing to SCL.

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