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![Keith Randall](/assets/img/avatar_default.png)
if q != nil { p = &q.f } Which gets rewritten to a conditional move: tmp := &q.f p = Select q!=nil, tmp, p Unfortunately, we can't compute &q.f before we've checked if q is nil, because if it is nil, &q.f is an invalid pointer (if f's offset is nonzero but small). Normally this is not a problem because the tmp variable above immediately dies, and is thus not live across any safepoint. However, if later there is another &q.f computation, those two computations are CSEd, causing tmp to be used at both use points. That will extend tmp's lifetime, possibly across a call. Fixes #56990 Change-Id: I3ea31be93feae04fbe3304cb11323194c5df3879 Reviewed-on: https://go-review.googlesource.com/c/go/+/454155 TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com> Run-TryBot: Keith Randall <khr@golang.org> Reviewed-by: Keith Randall <khr@google.com>
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PASS
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