[clang] [llvm] [WPD] Support speculative devirtualization with LTO (PR #233380)

[via cfe-commits]

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@@ -1131,12 +1120,6 @@ bool DevirtModule::tryFindVirtualCallTargets(
     if (Fn->getName() == "__cxa_pure_virtual")
       continue;
 
-    // In most cases empty functions will be overridden by the
-    // implementation of the derived class, so we can skip them.
-    if (DevirtSpeculatively && Fn->getReturnType()->isVoidTy() &&
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KRM7 wrote:

For example, this program would be miscompiled and would return 1 instead of 0 if we kept the check in this patch: https://godbolt.org/z/bedWzheTj

https://github.com/llvm/llvm-project/pull/233380