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Bug 1861276
Summary: | LTO breaks tpm2-pkcs11 build | ||
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Product: | [Fedora] Fedora | Reporter: | Dan Horák <dan> |
Component: | gcc | Assignee: | Jeff Law <law> |
Status: | NEW --- | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
Severity: | unspecified | Docs Contact: | |
Priority: | unspecified | ||
Version: | 33 | CC: | aoliva, dmalcolm, fweimer, jakub, jwakely, law, mpolacek, msebor, nickc, pbrobinson, sipoyare |
Target Milestone: | --- | ||
Target Release: | --- | ||
Hardware: | s390x | ||
OS: | Unspecified | ||
Whiteboard: | |||
Fixed In Version: | Doc Type: | If docs needed, set a value | |
Doc Text: | Story Points: | --- | |
Clone Of: | Environment: | ||
Last Closed: | Type: | Bug | |
Regression: | --- | Mount Type: | --- |
Documentation: | --- | CRM: | |
Verified Versions: | Category: | --- | |
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
Cloudforms Team: | --- | Target Upstream Version: | |
Embargoed: | |||
Bug Depends On: | |||
Bug Blocks: | 467765, 1789115 |
Description
Dan Horák
2020-07-28 08:15:50 UTC
All kinds of interesting possibilities here, I'm sure the unique inlining tuning on s390 comes into play. Thanks for passing it along. So this is a combination of LTO's cross-module inlining combined with a missed optimization computing ranges for integer overflow tests which results in an infeasible path being left in the CFG. On that infeasible path we have propagated a negative constant value into the size argument of a memset call and we get the bogus diagnostic. I've filed an upstream BZ for the missed optimization. There's actually a good chance this will be solvable with work that Andrew & Aldy are looking to land in gcc-11. In the immediate term, I think the s390 disablement of LTO is quite reasonable. This bug appears to have been reported against 'rawhide' during the Fedora 33 development cycle. Changing version to 33. |