[cxx-interop] Prevent protocol conformance table from being prematurely populated #83181
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…ly populated We've started seeing build failures where the conformance of a `std::vector` instantiation to `CxxVector` is missing. This was because the LifetimeDependenceInfoRequest triggers the protocol conformance table for the instantiation to be built before the synthesized conformance gets added. This works around the issue by preventing LifetimeDependenceInfoRequest from running for the synthesized default argument generator function, which was the culprit of this particular failure. rdar://155977071
egorzhdan
requested review from
beccadax,
ian-twilightcoder,
Xazax-hun,
j-hui,
fahadnayyar and
susmonteiro
as code owners
|
@swift-ci please smoke test |
you’re adding the synthesized conformance in the wrong place. |
Xazax-hun
approved these changes
Jul 21, 2025
|
This fix looks reasonable for me for the acute issue. We talked offline about a couple of potential alternative solutions but I think it is OK to explore those in follow-up PRs. |
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We've started seeing build failures where the conformance of a
std::vectorinstantiation toCxxVectoris missing. This was because the LifetimeDependenceInfoRequest triggers the protocol conformance table for the instantiation to be built before the synthesized conformance gets added.This works around the issue by preventing LifetimeDependenceInfoRequest from running for the synthesized default argument generator function, which was the culprit of this particular failure.
rdar://155977071