[PATCH] D137381: [clang][compiler-rt] Exception escape out of an non-unwinding function is an undefined behaviour

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri marked an inline comment as done.
lebedev.ri added inline comments.


================
Comment at: clang/lib/CodeGen/CGCall.cpp:5402-5411
+    if (SanOpts.has(SanitizerKind::ExceptionEscape) &&
+        ExceptionEscapeUBLastInvokeSrcLoc) {
+      llvm::Constant *CheckSourceLocation = EmitCheckSourceLocation(Loc);
+      Builder.CreateStore(
+          CheckSourceLocation,
+          Address(ExceptionEscapeUBLastInvokeSrcLoc,
+                  CheckSourceLocation->getType(),
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@rjmccall
So there are two issues:
1. `getInvokeDest()` isn't necessarily called just before creating an `invoke`, see e.g. `-EHa` handling in `CodeGenFunction::PopCleanupBlock()`
2. Even if we ignore that, we need to do this for *every* `invoke`, not just those going to the our UB landing pad, consider: https://godbolt.org/z/qTeKor41a <- the invoke leads to a normal landing pad, yet we immediately rethrow the just-caught exception, and now end up in the UB landing pad.

So i'm not really seeing an alternative path here?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D137381/new/

https://reviews.llvm.org/D137381