[clang] nonblocking/nonallocating attributes (was: nolock/noalloc) (PR #84983)

[Doug Wyatt via cfe-commits]

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@@ -10510,6 +10512,8 @@ QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs,
     if (lproto->getMethodQuals() != rproto->getMethodQuals())
       return {};
 
+    // TODO: (nonblocking) Does anything need to be done with FunctionEffects?
+
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dougsonos wrote:

I managed to refresh my memory of when this can be called -- it's in C, for redeclarations with attribute mismatches, and in situations like trying to build a type for the result of a conditional expression. There's a good example with how this method handles `noreturn`, which I'll copy.

https://github.com/llvm/llvm-project/pull/84983