https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125509
Bug ID: 125509
Summary: [17 regression] ICE when building llvm-20.1.8
(dominator of .. should be .., not ..,
verify_dominators, at dominance.cc:1194)
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Keywords: ice-checking, ice-on-valid-code
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: sjames at gcc dot gnu.org
Target Milestone: ---
Created attachment 64587
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=64587&action=edit
MCAsmStreamer.cpp.ii.xz
```
$ g++ -c ./lib/MC/CMakeFiles/LLVMMC.dir/MCAsmStreamer.cpp.ii -O3 -std=gnu++17
-march=x86-64-v2
/var/tmp/portage/llvm-core/llvm-20.1.8/work/llvm/lib/MC/MCAsmStreamer.cpp: In
member function ‘virtual void
{anonymous}::MCAsmStreamer::emitBytes(llvm::StringRef)’:
/var/tmp/portage/llvm-core/llvm-20.1.8/work/llvm/lib/MC/MCAsmStreamer.cpp:1282:6:
error: dominator of 34 should be 5, not 58
1282 | void MCAsmStreamer::emitBytes(StringRef Data) {
| ^~~~~~~~~~~~~
during GIMPLE pass: vect
/var/tmp/portage/llvm-core/llvm-20.1.8/work/llvm/lib/MC/MCAsmStreamer.cpp:1282:6:
internal compiler error: in verify_dominators, at dominance.cc:1194
0x557b869e999e internal_error(char const*, ...)
/usr/src/debug/sys-devel/gcc-17.0.9999/gcc-17.0.9999/gcc/diagnostic-global-context.cc:787
0x557b869e9b41 fancy_abort(char const*, int, char const*)
/usr/src/debug/sys-devel/gcc-17.0.9999/gcc-17.0.9999/gcc/diagnostics/context.cc:1813
0x557b84eee087 verify_dominators(cdi_direction) [clone .constprop.0]
/usr/src/debug/sys-devel/gcc-17.0.9999/gcc-17.0.9999/gcc/dominance.cc:1194
0x557b879a7e94 checking_verify_dominators(cdi_direction)
/usr/src/debug/sys-devel/gcc-17.0.9999/gcc-17.0.9999/gcc/dominance.h:76
0x557b879a7e94 cleanup_tree_cfg_noloop
/usr/src/debug/sys-devel/gcc-17.0.9999/gcc-17.0.9999/gcc/tree-cfgcleanup.cc:1239
0x557b86d477f8 cleanup_tree_cfg(unsigned int)
/usr/src/debug/sys-devel/gcc-17.0.9999/gcc-17.0.9999/gcc/tree-cfgcleanup.cc:1337
0x557b86d477f8 execute_function_todo
/usr/src/debug/sys-devel/gcc-17.0.9999/gcc-17.0.9999/gcc/passes.cc:2069
0x557b86bb7781 do_per_function
/usr/src/debug/sys-devel/gcc-17.0.9999/gcc-17.0.9999/gcc/passes.cc:1699
0x557b86bb7781 execute_todo
/usr/src/debug/sys-devel/gcc-17.0.9999/gcc-17.0.9999/gcc/passes.cc:2152
/usr/libexec/gcc/x86_64-pc-linux-gnu/17/cc1plus -fpreprocessed
./lib/MC/CMakeFiles/LLVMMC.dir/MCAsmStreamer.cpp.ii -quiet -dumpbase
MCAsmStreamer.cpp.ii -dumpbase-ext .ii -march=x86-64-v2 -mtls-dialect=gnu2 -O3
-std=gnu++17 -foffload-options=-fno-stack-protector -fcf-protection
-foffload-options=-fcf-protection=none -o /tmp/ccOPpUru.s
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.
```
```
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-pc-linux-gnu/17/lto-wrapper
OFFLOAD_TARGET_NAMES=nvptx-none
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-pc-linux-gnu
Configured with:
/var/tmp/portage/sys-devel/gcc-17.0.9999/work/gcc-17.0.9999/configure
--host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --prefix=/usr
--bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/17
--includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/17/include
--datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/17
--mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/17/man
--infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/17/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/17/include/g++-v17
--disable-silent-rules --disable-dependency-tracking
--with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/17/python
--enable-libphobos --enable-objc-gc
--enable-languages=c,c++,d,objc,obj-c++,fortran,ada,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 17.0.9999 p, commit
779783c7301297c6aeb6def4da48c44f4ae46782' --with-gcc-major-version-only
--enable-libstdcxx-time --enable-lto --disable-libstdcxx-pch
--enable-linker-build-id --enable-libada --enable-shared --enable-threads=posix
--enable-__cxa_atexit --enable-clocale=gnu --with-tls=gnu2 --enable-multilib
--with-multilib-list=m32,mx32,m64 --disable-fixed-point --with-abi=m64
--enable-targets=all --enable-offload-defaulted
--enable-offload-targets=nvptx-none --enable-libgomp --disable-libssp
--enable-cet --disable-systemtap --enable-valgrind-annotations
--enable-valgrind-interop --disable-vtable-verify --disable-libvtv --with-zstd
--without-isl --enable-default-pie --enable-host-pie --enable-host-bind-now
--enable-default-ssp --disable-fixincludes
--with-gxx-libcxx-include-dir=/usr/include/c++/v1
--with-build-config='bootstrap-O3 bootstrap-lto bootstrap-cet'
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 17.0.0 20260529 (experimental)
cdaec79820fd6f9c2e1fee38d8f543a4e2db7528 (Gentoo 17.0.9999 p, commit
779783c7301297c6aeb6def4da48c44f4ae46782)
```
