| Summary: | dev-ros/stereo_image_proc-1.16.0 fails to compile (lto): processor.cpp:181:48: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing] | ||
|---|---|---|---|
| Product: | Gentoo Linux | Reporter: | Agostino Sarubbo <ago> |
| Component: | Current packages | Assignee: | Robot Operating System team <ros> |
| Status: | RESOLVED OBSOLETE | ||
| Severity: | normal | ||
| Priority: | Normal | ||
| Version: | unspecified | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Package list: | Runtime testing required: | --- | |
| Bug Depends on: | |||
| Bug Blocks: | 618550 | ||
| Attachments: | build.log | ||
|
Description
Agostino Sarubbo
2022-07-11 07:11:03 UTC
Created attachment 790973 [details]
build.log
build log and emerge --info
Error(s) that match a know pattern in addition to what has been reported in the summary: FAILED: CMakeFiles/stereo_image_proc.dir/src/libstereo_image_proc/processor.cpp.o /var/tmp/portage/dev-ros/stereo_image_proc-1.16.0/work/image_pipeline-1.16.0/stereo_image_proc/src/libstereo_image_proc/processor.cpp:181:48: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing] Here is a bit of explanation: -Werror=lto-type-mismatch: User to find possible runtime issues in packages. It likely means the package is unsafe to build & use with LTO. For projects using the same identifier but with different types across different files, they must be fixed to be consistent across the codebase. -Werror=odr: Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO. C++ code must comply with the One Definition Rule (ODR) - see https://en.cppreference.com/w/cpp/language/definition#One_Definition_Rule. -Werror=strict-aliasing: Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO. Workarounds: - If upstream is friendly and still active, file a bug upstream. For emulators, codecs, games, or multimedia packages, it may be worth just applying a workaround instead, as upstreams sometimes aren't receptive to these bugs (VALID FOR ALL). - Use the new 'filter-lto' from flag-o-matic.eclass as it's likely to be unsafe with LTO (VALID FOR lto-type-mismatch - odr). - Fix it yourself if interested, of course (VALID FOR ALL). - Append-flags -fno-strict-aliasing (VALID FOR strict-aliasing). - Use memcpy() but a union is sometimes suitable too (VALID FOR strict-aliasing). - -fstrict-aliasing is implied by -O2, so this must be addressed in some form (VALID FOR strict-aliasing). See also: https://marc.info/?l=gentoo-dev&m=165639574126280&w=2 Package removed. |
