Bug 951445 – llvm-runtimes/libcxxabi-20.1.0 [clang, musl]: dependencies lead to missing /etc/clang from changes to llvm-core/clang-common and llvm-core/clang-runtime (error: cannot open crtbeginS.o: No such file or directory)

• Status: UNCONFIRMED
• Product: Gentoo Linux

[Description scv 2025-03-16 04:32:34 UTC]

Created attachment 920883 [details]
build.log

# emerge --info
!!! No gcc found. You probably need to 'source /etc/profile'
!!! to update the environment of this terminal and possibly
!!! other terminals also.
Portage 3.0.67 (python 3.12.9-final-0, default/linux/amd64/23.0/musl/llvm, [unavailable], musl-1.2.5-r3, 6.12.16 x86_64)
=================================================================
System uname: Linux-6.12.16-x86_64-AMD_Ryzen_7_5800X_8-Core_Processor-with-libc
KiB Mem:    32755952 total,  28193484 free
KiB Swap:          0 total,         0 free
Timestamp of repository gentoo: Sun, 16 Mar 2025 02:15:00 +0000
Head commit of repository gentoo: 9351b4ba0c25403cd3b0025a360407e00ed72024
sh bash 5.2_p37
app-misc/pax-utils:       1.3.8::gentoo
app-shells/bash:          5.2_p37::gentoo
dev-build/autoconf:       2.72-r1::gentoo
dev-build/automake:       1.16.5-r2::gentoo, 1.17-r2::gentoo
dev-build/cmake:          3.31.6-r1::gentoo
dev-build/libtool:        2.5.4::gentoo
dev-build/make:           4.4.1-r100::gentoo
dev-build/meson:          1.7.0::gentoo
dev-lang/perl:            5.40.1::gentoo
dev-lang/python:          3.12.9::gentoo, 3.13.2::gentoo
llvm-core/clang:          19.1.7::gentoo, 20.1.0-r1::gentoo
llvm-core/lld:            19.1.7::gentoo, 20.1.0::gentoo
llvm-core/llvm:           19.1.7::gentoo, 20.1.0::gentoo
sys-apps/baselayout:      2.17::gentoo
sys-apps/openrc:          0.60.1::gentoo
sys-apps/sandbox:         2.45::gentoo
sys-kernel/linux-headers: 6.13::gentoo (virtual/os-headers)
sys-libs/musl:            1.2.5-r3::gentoo
Repositories:

gentoo
    location: /var/db/repos/gentoo
    sync-type: rsync
    sync-uri: rsync://rsync.gentoo.org/gentoo-portage
    priority: -1000
    volatile: False
    sync-rsync-verify-metamanifest: yes
    sync-rsync-extra-opts: 
    sync-rsync-verify-jobs: 1
    sync-rsync-verify-max-age: 3

Binary Repositories:

gentoobinhost
    priority: 1
    sync-uri: https://distfiles.gentoo.org/releases/amd64/binpackages/23.0/x86-64_musl_llvm

ACCEPT_KEYWORDS="amd64 ~amd64"
ACCEPT_LICENSE="*"
ADDR2LINE="llvm-addr2line"
AR="llvm-ar"
AS="clang -c"
CBUILD="x86_64-pc-linux-musl"
CC="clang"
CFLAGS="-march=native -O3 -flto=thin -pipe"
CHOST="x86_64-pc-linux-musl"
CONFIG_PROTECT="/etc /usr/share/gnupg/qualified.txt /var/bind"
CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/gconf /etc/gentoo-release /etc/sandbox.d"
CPP="clang-cpp"
CXX="clang++"
CXXFLAGS="-march=native -O3 -flto=thin -pipe"
DISTDIR="/var/cache/distfiles"
ENV_UNSET="CARGO_HOME DBUS_SESSION_BUS_ADDRESS DISPLAY GDK_PIXBUF_MODULE_FILE GOBIN GOPATH PERL5LIB PERL5OPT PERLPREFIX PERL_CORE PERL_MB_OPT PERL_MM_OPT XAUTHORITY XDG_CACHE_HOME XDG_CONFIG_HOME XDG_DATA_HOME XDG_RUNTIME_DIR XDG_STATE_HOME"
FCFLAGS="-march=native -O3 -flto=thin -pipe"
FEATURES="assume-digests binpkg-docompress binpkg-dostrip binpkg-logs binpkg-multi-instance buildpkg-live config-protect-if-modified distlocks ebuild-locks fixlafiles ipc-sandbox merge-sync merge-wait network-sandbox news parallel-fetch pid-sandbox pkgdir-index-trusted preserve-libs protect-owned qa-unresolved-soname-deps sandbox strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync xattr"
FFLAGS="-march=native -O3 -flto=thin -pipe"
GENTOO_MIRRORS="http://distfiles.gentoo.org"
INSTALL_MASK="charset.alias /usr/share/locale/locale.alias"
LANG="C.UTF8"
LD="ld.lld"
LDFLAGS="-Wl,-O1 -Wl,--as-needed -Wl,-z,pack-relative-relocs -Wl,--as-needed"
LEX="flex"
MAKEOPTS="-j16"
NM="llvm-nm"
OBJCOPY="llvm-objcopy"
OBJDUMP="llvm-objdump"
PKGDIR="/var/cache/binpkgs"
PORTAGE_COMPRESS="zstd"
PORTAGE_CONFIGROOT="/"
PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages --exclude=/.git"
PORTAGE_TMPDIR="/var/tmp"
RANLIB="llvm-ranlib"
READELF="llvm-readelf"
RUSTFLAGS="-C target-cpu=native -C linker-plugin-lto"
SHELL="/bin/bash"
STRINGS="llvm-strings"
STRIP="llvm-strip"
USE="acl amd64 bzip2 caps cet clang crypt dist-kernel iconv ipv6 libtirpc llvm-libunwind lto ncurses nls openmp pam pcre pic pipewire pulseaudio readline seccomp ssl test-rust unicode vaapi xattr zlib zstd" ABI_X86="64" ADA_TARGET="gcc_14" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd actions alias auth_basic authn_anon authn_dbm authn_file authz_dbm authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir env expires ext_filter file_cache filter headers include info log_config logio mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" CALLIGRA_FEATURES="karbon sheets words" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" CPU_FLAGS_X86="mmx mmxext sse sse2 aes avx avx2 f16c fma3 pclmul popcnt rdrand sha sse3 sse4_1 sse4_2 sse4a ssse3 vpclmulqdq" ELIBC="musl" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock greis isync itrax navcom oceanserver oncore rtcm104v2 rtcm104v3 sirf skytraq superstar2 tsip tripmate tnt ublox" GUILE_SINGLE_TARGET="3-0" GUILE_TARGETS="3-0" INPUT_DEVICES="libinput" KERNEL="linux" LCD_DEVICES="bayrad cfontz glk hd44780 lb216 lcdm001 mtxorb text" LLVM_SLOT="20" LUA_SINGLE_TARGET="lua5-1" LUA_TARGETS="lua5-1" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php8-2" POSTGRES_TARGETS="postgres16" PYTHON_SINGLE_TARGET="python3_12" PYTHON_TARGETS="python3_12" RUBY_TARGETS="ruby32" VIDEO_CARDS="amdgpu radeonsi" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipp2p iface geoip fuzzy condition tarpit sysrq proto logmark ipmark dhcpmac delude chaos account"
Unset:  ARFLAGS, ASFLAGS, CCLD, CONFIG_SHELL, CPPFLAGS, CTARGET, CXXFILT, ELFEDIT, EMERGE_DEFAULT_OPTS, EXTRA_ECONF, F77FLAGS, FC, GCOV, GPROF, LC_ALL, LFLAGS, LIBTOOL, LINGUAS, MAKE, MAKEFLAGS, PORTAGE_BINHOST, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, PYTHONPATH, SIZE, YACC, YFLAGS

[Comment 1 scv 2025-03-16 05:00:52 UTC]

Perhaps related to this?
https://github.com/llvm/llvm-project/issues/93502

[Comment 2 Sam James 2025-03-31 20:29:07 UTC]

As discussed on IRC, this is what vimproved mentioned before:
<vimproved>  correct me if i'm wrong here, but with the per-slot config files I think there's going to be an issue with the fact that clang-runtime is always merged after clang
<vimproved>  so there's a period where between merging clang and clang-runtime, the toolchain is not using any config file and therefor could be broken
<vimproved>  and to merge clang-runtime you may need to compile a new version of compiler-rt, which wants to be compiled with the new version of clang

i.e. it's a transient failure depending on merge order, and caused by the change to slotted Clang config with LLVM 20 (because we changed with things moving to llvm-core/clang-runtime, see 48f104e91c85fe0f6642f17f8e0652e086f63b82 and  27ba83267d59df328e1ef409f96ef16844bd26a8).

I'm not yet sure how to work around it or fix it properly.