https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120629
Bug ID: 120629
Summary: [16 regression] bootstrap-lto fails
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Keywords: build
Severity: normal
Priority: P3
Component: ipa
Assignee: unassigned at gcc dot gnu.org
Reporter: sjames at gcc dot gnu.org
Target Milestone: ---
I'll get a simpler recipe to reproduce now.
```
# /var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/./prev-gcc/xg++
-B/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/./prev-gcc/
-B/usr/x86_64-pc-linux-gnu/bin/ -nostdinc++
-B/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
-B/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
-I/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/prev-x86_64-pc-linux-gnu/libstdc++-v3/include/x86_64-pc-linux-gnu
-I/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/prev-x86_64-pc-linux-gnu/libstdc++-v3/include
-I/var/tmp/portage/sys-devel/gcc-16.0.9999/work/gcc-16.0.9999/libstdc++-v3/libsupc++
-L/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
-L/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
-DDEF_GENTOO_SCP -DDEF_GENTOO_ZNOW -DEXTRA_OPTIONS
-DGENTOO_FORTIFY_SOURCE_LEVEL=3 -DDEF_GENTOO_GLIBCXX_ASSERTIONS -m64 -O3
-march=native -mtls-dialect=gnu2 -fno-semantic-interposition -g1 -pipe
-fcf-protection=none -fdiagnostics-color=always -fdiagnostics-urls=never
-fdiagnostics-set-output=text:experimental-nesting=yes -Wa,-O2
-Wa,-mtune=znver2 --param=ggc-min-expand=120 -Wstrict-aliasing
-Wfree-nonheap-object -Wuninitialized -Wmaybe-uninitialized -Wreturn-type
-Wbuiltin-declaration-mismatch -Wtautological-compare -Werror=lto-type-mismatch
-Werror=strict-aliasing -Werror=odr -Wstringop-overread -Wstringop-overflow
-Wstringop-truncation -Wformat-overflow -Wformat-truncation -ggdb3
-Wno-error=lto-type-mismatch -Wno-error=odr -flto=jobserver -frandom-seed=1
-flto=jobserver -frandom-seed=1 -DIN_GCC -fno-exceptions -fno-rtti
-fasynchronous-unwind-tables -W -Wall -Wno-error=narrowing -Wwrite-strings
-Wcast-qual -Wmissing-format-attribute -Wconditionally-supported
-Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros
-Wno-overlength-strings -DHAVE_CONFIG_H -DGENERATOR_FILE -static-libstdc++
-static-libgcc -Wl,-m -Wl,elf_x86_64 -O3 -march=native -mtls-dialect=gnu2
-fno-semantic-interposition -g1 -pipe -fcf-protection=none
-fdiagnostics-color=always -fdiagnostics-urls=never
-fdiagnostics-set-output=text:experimental-nesting=yes -Wa,-O2
-Wa,-mtune=znver2 --param=ggc-min-expand=120 -Werror=lto-type-mismatch
-Werror=strict-aliasing -Werror=odr -Wstringop-overread -Wstringop-overflow
-Wstringop-truncation -Wformat-overflow -Wformat-truncation -Wl,-O1
-Wl,--as-needed -Wl,-z,pack-relative-relocs
-Wl,--defsym=__gentoo_check_ldflags__=0 -ggdb3 -Wno-error=lto-type-mismatch
-Wno-error=odr -o build/gengtype build/gengtype.o build/errors.o
build/gengtype-lex.o build/gengtype-parse.o build/gengtype-state.o
.././libiberty/libiberty.a
during IPA pass: fnsummary
lto1: internal compiler error: Segmentation fault
0x55bf3a0ec5f5 internal_error(char const*, ...)
/var/tmp/portage/sys-devel/gcc-16.0.9999/work/gcc-16.0.9999/gcc/diagnostic-global-context.cc:517
0x55bf36e2bae4 crash_signal
/var/tmp/portage/sys-devel/gcc-16.0.9999/work/gcc-16.0.9999/gcc/toplev.cc:322
0x7f2cbb4201bf ???
/usr/src/debug/sys-libs/glibc-2.41.9999/glibc-2.41.9999/signal/../sysdeps/unix/sysv/linux/x86_64/libc_sigaction.c:0
0x55bf3661d74a ipa_predicate::stream_in(lto_input_block*)
/var/tmp/portage/sys-devel/gcc-16.0.9999/work/gcc-16.0.9999/gcc/ipa-predicate.cc:614
0x55bf3659d56a inline_read_section
/var/tmp/portage/sys-devel/gcc-16.0.9999/work/gcc-16.0.9999/gcc/ipa-fnsummary.cc:4863
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://bugs.gentoo.org/> for instructions.
lto-wrapper: fatal error:
/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/./prev-gcc/xg++ returned 1
exit status
compilation terminated.
/usr/x86_64-pc-linux-gnu/bin/ld: error: lto-wrapper failed
```
```
$ /var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/./prev-gcc/xg++ -v
Using built-in specs.
COLLECT_GCC=/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/./prev-gcc/xg++
OFFLOAD_TARGET_NAMES=nvptx-none
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-pc-linux-gnu
Configured with:
/var/tmp/portage/sys-devel/gcc-16.0.9999/work/gcc-16.0.9999/configure
--host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --prefix=/usr
--bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/16
--includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/16/include
--datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/16
--mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/16/man
--infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/16/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/16/include/g++-v16
--disable-silent-rules --disable-dependency-tracking
--with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/16/python
--enable-libphobos --enable-objc-gc
--enable-languages=c,c++,d,objc,obj-c++,fortran,ada,cobol,m2,rust
--enable-obsolete --enable-secureplt --disable-werror --with-system-zlib
--enable-nls --without-included-gettext --disable-libunwind-exceptions
--enable-checking=yes,extra,rtl --with-bugurl=https://bugs.gentoo.org/
--with-pkgversion='Gentoo Hardened 16.0.9999 p, commit
eb54dc3c87cb5c11faff6dbd447641d13e6fdaf1' --with-gcc-major-version-only
--enable-libstdcxx-time --enable-lto --disable-libstdcxx-pch --enable-shared
--enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu
--enable-multilib --with-multilib-list=m32,m64 --disable-fixed-point
--enable-targets=all --enable-offload-defaulted
--enable-offload-targets=nvptx-none --enable-libgomp --disable-libssp
--enable-libada --disable-cet --disable-systemtap --enable-valgrind-annotations
--disable-vtable-verify --disable-libvtv --with-zstd --with-isl
--disable-isl-version-check --enable-default-pie --enable-host-pie
--enable-host-bind-now --enable-default-ssp --disable-fixincludes
--with-gxx-libcxx-include-dir=/usr/include/c++/v1 --enable-linker-build-id
--with-build-config='bootstrap-O3 bootstrap-lto'
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 16.0.0 20250611 (experimental)
2c3ce07c568037a085bfcc438e2e823060980225 (Gentoo Hardened 16.0.9999 p, commit
eb54dc3c87cb5c11faff6dbd447641d13e6fdaf1)
```
