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[cmake] Check std::vector layout - #24000
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Found by compiling with clang/libc++ on Linux.
Test Results 21 files 21 suites 3d 10h 30m 55s ⏱️ Results for commit c9e9035. ♻️ This comment has been updated with latest results. |
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The std::vector layout, currently, uses three pointers (begin, end, end of capacity). This is used by the ROOT I/O to work with vectors of anything by treating any vector as a vector<char>. The approach breaks, however, with the std::vector layout in the libc++ unstable ABI that implements vector with one pointer and two integers.
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The std::vector layout, currently, uses three pointers (begin, end, end
of capacity). This is used by the ROOT I/O to work with vectors of
anything by treating any vector as a vector. The approach breaks,
however, with the std::vector layout in the libc++ unstable ABI that
implements vector with one pointer and two integers.
See also https://discourse.llvm.org/t/adding-a-size-based-vector-to-libc-s-unstable-abi/86306
Tested on Linux with clang 23 and latest libc++ built from sources.