On Thu, Oct 20, 2022 at 9:56 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > > On Wed, Oct 19, 2022 at 10:44 PM Sedat Dilek (DHL Supply Chain) > <sedat.dilek@xxxxxxx> wrote: > > > > -----Ursprüngliche Nachricht----- > > Von: Sami Tolvanen <samitolvanen@xxxxxxxxxx> > > Gesendet: Dienstag, 18. Oktober 2022 18:00 > > An: Sedat Dilek (DHL Supply Chain) <sedat.dilek@xxxxxxx> > > Betreff: Re: Update15.x/kcfi to LLVM 15.0.3 > > > > On Tue, Oct 18, 2022 at 4:54 AM Sedat Dilek (DHL Supply Chain) <sedat.dilek@xxxxxxx> wrote: > > > > > [ CC Nick + Fangrui ] > > > > You happen to know or use the ZSTD cmake-option (see [1] and [2]) - came in with changes post-15.0.2? > > > > AFAICS Fangrui Song had some patches to use ZSTD debug-compression with DWARFv5. > > > > Unsure, if that combination is now possible in v15.0.3 or is a feature of LLVM-16. > > > > [3] says: > > > > [ lib/Kconfig.debug ] > > > > config DEBUG_INFO_COMPRESSED > > bool "Compressed debugging information" > > depends on $(cc-option,-gz=zlib) > > depends on $(ld-option,--compress-debug-sections=zlib) > > help > > Compress the debug information using zlib. Requires GCC 5.0+ or Clang > > 5.0+, binutils 2.26+, and zlib. > > > > Users of dpkg-deb via scripts/package/builddeb may find an increase in > > size of their debug .deb packages with this config set, due to the > > debug info being compressed with zlib, then the object files being > > recompressed with a different compression scheme. But this is still > > preferable to setting $KDEB_COMPRESS to "none" which would be even > > larger. > > > > I am interested in the equivalent changes to cc-option/ld-option with ZSTD (usable with DWARFv5). > > Good idea. It looks like there's still a blocker to using -gz=zstd with clang: > $ clang -gz=zstd -x c - < /dev/null > clang-16: warning: cannot compress debug sections (zstd not enabled) > [-Wdebug-compression-unavailable] PEBKAC $ sudo apt install libzstd-dev <rebuild clang> > > https://github.com/facebook/zstd/issues/3271 > > Attaching a WIP patch. > > > > > Thanks. > > > > Best regards, > > -Sedat- > > > > [1] https://github.com/llvm/llvm-project/commit/6fba7854a2f0b6b3899bb156c1a0c4ae35c96e24 > > [2] https://github.com/llvm/llvm-project/commit/b4840279846e1eea44c3dca575395a90c9d77ca0 > > [3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/lib/Kconfig.debug#n315 > > [4] https://metadata.ftp-master.debian.org/changelogs//main/l/llvm-toolchain-15/llvm-toolchain-15_15.0.3-1~exp1_changelog > > > > > > > > > -- > Thanks, > ~Nick Desaulniers -- Thanks, ~Nick Desaulniers
