Backport main changes to the hiperf branch and LLD fix
#165
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Previously has_tag reported true, even if the specified template had members (depending on the template arguments) that did not have a tag.
Use Clang, because GitHub Ubuntu latest image has gcc 9, that does not support concepts. clang 10 should have a better support. - https://gcc.gnu.org/projects/cxx-status.html - https://clang.llvm.org/cxx_status.html
Use cmake options (defaulting to on) for the bread and brecovery binaries, as well as the tests and examples. This aids installation of binlog through vcpkg.
Newly disabled checks:
bugprone-easily-swappable-parameters
google-readability-casting
modernize-use-default-member-init
readability-identifier-length
The diff is bigger, as the checklist is now sorted.
erenon
changed the title
main changes to the hiperf branchmain changes to the hiperf branch and LLD fix
In our custom ELF section, .binlog.esrc, we are storing 8 pointers/EventSource, see create_source.hpp. Previously, we listed the loaded files, and extracted these pointers from the on-disk files where the program was loaded from. GNU ld and gold sets these pointers build time to offsets in the file, that are relocated load time. lld, however, leaves them blank, a different kind of relocation is used instead. Therefore, we have to get the sources from memory, instead of disk. We are using dl_iterate_phdr to get the list of loaded objects + their load address. The program headers reference segments, a set of mapped sections. Unfortunately, I wasn't able to find the section headers in memory (probably it isn't there), so we still need to read the original file, find our custom section, and map it to a loaded segment. Since we are reading the pointers from loaded memory, our section must be "allocated". Since it contains relocations, it must be marked as writable, otherwise the linker warns: "relocation in read-only section `.binlog.esrc'". Therefore, we add "wa" to the .pushsection directive. A range-check bug in the original implementation was found and fixed by Eric Harding, that triggered the investigation that ended with this fix - thanks!
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@spektrof PTAL and merge, thanks! |
spektrof
approved these changes
Apr 24, 2023
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This should also fix the CI.