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[clang] Fix a use-after-free in expression evaluation #118480

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[clang] Fix a use-after-free in expression evaluation #118480

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2 changes: 2 additions & 0 deletions clang/lib/AST/ExprConstant.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -4515,6 +4515,8 @@ handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv, QualType Type,
}

APValue Lit;
// Make sure we clean up the temporary created below.
FullExpressionRAII CleanupTemps(Info);
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Could we get a reduced test case?

I don't think it's correct to do the cleanups here, we could probably construct some examples that break after this change.

There are ExprWithCleanups and various other mechanisms that ensure we do all the cleanups correctly. This delayed evaluation of compound literals might not play well with those cases today, but it's hard to know for sure without understanding the full picture. Having an example would help better understand if there's a fix needed in a different place.

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we could probably construct some examples that break after this change.

fair enough, i am not sure about the change either. wanted to throw it out to get some more thoughts from community.

Could we get a reduced test case?

i hope so. i am still running a creduce, file is still too big though :(

if (!Evaluate(Lit, Info, CLE->getInitializer()))
return false;

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