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This was referenced Sep 25, 2026
maleadt
added this pull request to stack #29
September 25, 2026 13:30
maleadt
marked this pull request as ready for review
September 25, 2026 15:11
`fence(unordered)` raised its error by calling `Core.Intrinsics.atomic_fence(:unordered)`, which throws a ConcurrencyViolationError. Julia's inference however assumes the intrinsic throws an ErrorException, and Julia 1.11 compiles `catch` blocks around it accordingly: the caught error is rebuilt as an ErrorException, and code specialized on that assumption, like a failing `@test_throws`, corrupts memory. This crashed the test suite on 1.11 intermittently. Throw the ConcurrencyViolationError directly instead, on every Julia version, so that inference sees the actual exception.
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fence(unordered) is caught
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Stack: bottom of the stack; #25 builds on this.
fence(unordered)should throw aConcurrencyViolationError. It did so by callingCore.Intrinsics.atomic_fence(:unordered), but Julia's inference assumes that intrinsic throws anErrorException. Julia 1.11 trusts that assumption incatchblocks and treats the caught error as the wrong type, so catching it (e.g. with@test_throws) can corrupt memory. This caused the intermittent segfaults and GC crashes in our test suite on 1.11, present since 0.3.2.This PR throws the error directly instead. Nothing else changes. The underlying Julia bug is JuliaLang/julia#63357, with a fix in JuliaLang/julia#63360.