lxfind added a comment. In D89066#2324291 <https://reviews.llvm.org/D89066#2324291>, @junparser wrote:
> In D89066#2324151 <https://reviews.llvm.org/D89066#2324151>, @lxfind wrote: > >> In D89066#2324115 <https://reviews.llvm.org/D89066#2324115>, @junparser >> wrote: >> >>> why we should not do this with normal await call? >> >> To be honest, I don't know yet. My understanding of how expression cleanup >> and temp lifetime management is insufficient at the moment. >> But first of all, without adding any cleanup expression here, I saw ASAN >> failures due to heap-use-after-free, because sometimes the frame have >> already been destroyed after the await_suspend call, and yet we are still >> writing into the frame due to unnecessarily cross-suspend lifetime. However, >> if I apply the cleanup to all await_suepend calls, it also causes ASAN >> failures as it's cleaning up data that's still alive. >> So this patch is more of a temporary walkaround to stop bleeding without >> causing any trouble. >> I plan to get back to this latter after I am done with the spilling/alloca >> issues. > > I'm not familiar with ASAN instrumentation. Do you have any testcases to > explain this? Unfortunately I don't. But this is not related to ASAN. Basically, this is causing destructing of objects that should still be alive. I suspect that it's because ExprWithCleanups always clean up temps that belongs to the full expression, not just the sub-expression in it. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D89066/new/ https://reviews.llvm.org/D89066 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
