[clang] nonblocking/nonallocating attributes: 2nd pass caller/callee analysis (PR #99656)

[Doug Wyatt via cfe-commits]

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@@ -8392,6 +8397,20 @@ void ASTReader::InitializeSema(Sema &S) {
         NewOverrides.applyOverrides(SemaObj->getLangOpts());
   }
 
+  if (!DeclsWithEffectsToVerify.empty()) {
+    for (GlobalDeclID ID : DeclsWithEffectsToVerify) {
+      Decl *D = GetDecl(ID);
+      FunctionEffectsRef FX;
+      if (auto *FD = dyn_cast<FunctionDecl>(D))
+        FX = FD->getFunctionEffects();
+      else if (auto *BD = dyn_cast<BlockDecl>(D))
+        FX = BD->getFunctionEffects();
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dougsonos wrote:

Yeah, it's guarding against a pathological case where a function or block in `DeclsWithEffectsToVerify` turns out to have no effects. It happens that (despite comments) `addDeclWithEffects()` will still guard against this, so OK.

https://github.com/llvm/llvm-project/pull/99656