https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125349
Bug ID: 125349
Summary: internal seg fault whilst building the Qt WebEngine
source code
Product: gcc
Version: 15.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: BT2023A at proton dot me
Target Milestone: ---
Dell Precision M6700 laptop, 24GB RAM, Intel® Core™ i7-3840QM × 8, Ubuntu 25.10
running 6.17.9 kernel (kernel built from source code).
g++ -v
Using built-in specs.
COLLECT_GCC=/usr/bin/g++
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-linux-gnu/15/lto-wrapper
OFFLOAD_TARGET_NAMES=nvptx-none:amdgcn-amdhsa
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 15.2.0-4ubuntu4'
--with-bugurl=file:///usr/share/doc/gcc-15/README.Bugs
--enable-languages=c,ada,c++,go,d,fortran,objc,obj-c++,m2,rust,cobol,algol68
--prefix=/usr --with-gcc-major-version-only --program-suffix=-15
--program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id
--libexecdir=/usr/libexec --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --enable-bootstrap --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes
--with-default-libstdcxx-abi=new --enable-libstdcxx-backtrace
--enable-gnu-unique-object --disable-vtable-verify --enable-plugin
--enable-default-pie --with-system-zlib --enable-libphobos-checking=release
--with-target-system-zlib=auto --enable-objc-gc=auto --enable-multiarch
--disable-werror --enable-cet --with-arch-32=i686 --with-abi=m64
--with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic
--enable-offload-targets=nvptx-none=/build/gcc-15-deiAlw/gcc-15-15.2.0/debian/tmp-nvptx/usr,amdgcn-amdhsa=/build/gcc-15-deiAlw/gcc-15-15.2.0/debian/tmp-gcn/usr
--enable-offload-defaulted --without-cuda-driver --enable-checking=release
--build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
--with-build-config=bootstrap-lto-lean --enable-link-serialization=2
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 15.2.0 (Ubuntu 15.2.0-4ubuntu4)
Requires Qt for development (ver 6.11.1) to be installed in order to configure
the build process later on.
Recently updated my Qt to latest version (Qt Creator 19.0.2, Built on
11/05/2026 08:32 based on Qt 6.10.3 (GCC 11.5.0 20240719 (Red Hat 11.5.0-11),
x86_64)).
I was attempting to build the Qt WebEngine source code (1st attempt takes 3
hours), eventually failing with internal seg fault.
Subsequent builds are faster to get to the seg fault failure.
(I'm not exactly familiar with the WebEngine build environment to know an
individual cli to generate the seg fault instantly, but the build does get
there eventually).
The terminal output for the last compile to seg fault is as follows....
[16942/24836] CXX
obj/third_party/blink/renderer/core/probe/instrumentation_probes/core_probes_impl.o
FAILED:
obj/third_party/blink/renderer/core/probe/instrumentation_probes/core_probes_impl.o
/usr/bin/g++ -MD -MF
obj/third_party/blink/renderer/core/probe/instrumentation_probes/core_probes_impl.o.d
-D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D_FILE_OFFSET_BITS=64
-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -DNO_UNWIND_TABLES
-D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_NONE -D_GLIBCXX_ASSERTIONS=1
-DUSE_UDEV -DUSE_AURA=1 -DUSE_OZONE=1 -DOFFICIAL_BUILD -DTOOLKIT_QT -DNDEBUG
-DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -DBLINK_CORE_IMPLEMENTATION=1
-DSK_ENABLE_SKSL -DSK_UNTIL_CRBUG_1187654_IS_FIXED
-DSK_USER_CONFIG_HEADER=\"../../skia/config/SkUserConfig.h\"
-DSK_WIN_FONTMGR_NO_SIMULATIONS -DSK_CODEC_DECODES_JPEG -DSK_CODEC_ENCODES_JPEG
-DSK_GAMMA_EXPONENT=1.2 -DSK_GAMMA_CONTRAST=0.2 -DSK_GANESH
-DSK_GPU_WORKAROUNDS_HEADER=\"gpu/config/gpu_driver_bug_workaround_autogen.h\"
-DSK_GL -DSK_VULKAN=1 -DSK_GRAPHITE -DCHROMIUM -DLIBYUV_DISABLE_NEON
-DLIBYUV_DISABLE_SVE -DLIBYUV_DISABLE_SME -DLIBYUV_DISABLE_LSX
-DLIBYUV_DISABLE_LASX -DBLINK_IMPLEMENTATION=1 -DINSIDE_BLINK
-DGOOGLE_PROTOBUF_NO_RTTI -DHAVE_PTHREAD -DU_USING_ICU_NAMESPACE=0
-DU_ENABLE_DYLOAD=0 -DUSE_CHROMIUM_ICU=1 -DU_ENABLE_TRACING=1
-DU_ENABLE_RESOURCE_TRACING=0 -DU_STATIC_IMPLEMENTATION
-DICU_UTIL_DATA_IMPL=ICU_UTIL_DATA_FILE
-DPROTOBUF_ENABLE_DEBUG_LOGGING_MAY_LEAK_PII=0 -DWEBRTC_CHROMIUM_BUILD
-DWEBRTC_POSIX -DWEBRTC_LINUX -DABSL_ALLOCATOR_NOTHROW=1
-DLOGGING_INSIDE_WEBRTC -DV8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT=0
-DV8_ARRAY_BUFFER_VIEW_INTERNAL_FIELD_COUNT=0
-DV8_PROMISE_INTERNAL_FIELD_COUNT=0 -DV8_USE_DEFAULT_HASHER_SECRET=true
-DV8_COMPRESS_POINTERS -DV8_COMPRESS_POINTERS_IN_SHARED_CAGE
-DV8_31BIT_SMIS_ON_64BIT_ARCH -DV8_ENABLE_SANDBOX -DV8_DEPRECATION_WARNINGS
-DV8_USE_PERFETTO -DV8_HAVE_TARGET_OS -DV8_TARGET_OS_LINUX -DCPPGC_CAGED_HEAP
-DCPPGC_YOUNG_GENERATION -DCPPGC_POINTER_COMPRESSION -DCPPGC_ENABLE_LARGER_CAGE
-DCPPGC_SLIM_WRITE_BARRIER -DFLATBUFFERS_LOCALE_INDEPENDENT=0
-DLEVELDB_PLATFORM_CHROMIUM=1 -DCRASHPAD_ZLIB_SOURCE_EXTERNAL
-DVK_NO_PROTOTYPES -DWTF_USE_WEBAUDIO_PFFFT=1 -DUSE_LIBJPEG_TURBO=1
-DMANGLE_JPEG_NAMES -DLIBXSLT_STATIC -Igen
-I../../../../../src/3rdparty/chromium
-I../../../../../src/3rdparty/chromium/third_party/perfetto/include
-Igen/third_party/perfetto/build_config -Igen/third_party/perfetto
-I../../../../../src/3rdparty/chromium/third_party/skia -Igen/third_party/skia
-I../../../../../src/3rdparty/chromium/third_party/wuffs/src/release/c
-I../../../../../src/3rdparty/chromium/third_party/vulkan-headers/src/include
-I../../../../../src/3rdparty/chromium/net/third_party/quiche/overrides
-I../../../../../src/3rdparty/chromium/net/third_party/quiche/src/quiche/common/platform/default
-I../../../../../src/3rdparty/chromium/net/third_party/quiche/src
-I../../../../../src/3rdparty/chromium/third_party/khronos
-I../../../../../src/3rdparty/chromium/gpu
-I../../../../../src/3rdparty/chromium/third_party/libyuv/include
-Igen/third_party/dawn/include
-I../../../../../src/3rdparty/chromium/third_party/dawn/include
-I../../../../../src/3rdparty/chromium/base/allocator/partition_allocator/src
-Igen/base/allocator/partition_allocator/src
-I../../../../../src/3rdparty/chromium/third_party/abseil-cpp
-I../../../../../src/3rdparty/chromium/third_party/boringssl/src/include
-I../../../../../src/3rdparty/chromium/third_party/protobuf/src
-Igen/net/third_party/quiche/src
-I../../../../../src/3rdparty/chromium/third_party/re2/src
-I../../../../../src/3rdparty/chromium/third_party/ipcz/include
-I../../../../../src/3rdparty/chromium/third_party/ced/src
-I../../../../../src/3rdparty/chromium/third_party/icu/source/common
-I../../../../../src/3rdparty/chromium/third_party/icu/source/i18n
-I../../../../../src/3rdparty/chromium/third_party/webrtc_overrides
-I../../../../../src/3rdparty/chromium/third_party/webrtc
-Igen/third_party/webrtc -I../../../../../src/3rdparty/chromium/v8/include
-I../../../../../src/3rdparty/chromium/third_party/flatbuffers/src/include
-I../../../../../src/3rdparty/chromium/third_party/flatbuffers/src/src
-I../../../../../src/3rdparty/chromium/third_party/flatbuffers/src
-I../../../../../src/3rdparty/chromium/third_party/flatbuffers/generated
-I../../../../../src/3rdparty/chromium/third_party/libwebm/source
-I../../../../../src/3rdparty/chromium/third_party/angle/include
-I../../../../../src/3rdparty/chromium/third_party/leveldatabase
-I../../../../../src/3rdparty/chromium/third_party/leveldatabase/src
-I../../../../../src/3rdparty/chromium/third_party/leveldatabase/src/include
-I../../../../../src/3rdparty/chromium/third_party/crashpad/crashpad
-I../../../../../src/3rdparty/chromium/third_party/crashpad/crashpad/compat/linux
-I../../../../../src/3rdparty/chromium/third_party/crashpad/crashpad/compat/non_win
-I../../../../../src/3rdparty/chromium/third_party/zlib
-I../../../../../src/3rdparty/chromium/third_party/libaom/source/libaom
-I../../../../../src/3rdparty/chromium/third_party/libaom/source/config/linux/x64
-I../../../../../src/3rdparty/chromium/third_party/libjpeg_turbo/src
-I../../../../../src/3rdparty/chromium/third_party/libpng
-I../../../../../src/3rdparty/chromium/third_party/ots/src/include
-Igen/v8/include
-I../../../../../src/3rdparty/chromium/third_party/fp16/src/include
-I../../../../../src/3rdparty/chromium/third_party/libxml/src/include
-I../../../../../src/3rdparty/chromium/third_party/libxml/linux/include
-I../../../../../src/3rdparty/chromium/third_party/libxslt/src
-I../../../../../src/3rdparty/chromium/third_party/libxslt/src/libxslt -Wall
-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -Wno-unused-local-typedefs
-Wno-maybe-uninitialized -Wno-deprecated-declarations
-fno-delete-null-pointer-checks -Wno-comments -Wno-packed-not-aligned
-Wno-misleading-indentation -Wno-dangling-else -Wno-missing-field-initializers
-Wno-unused-parameter -Wno-psabi -fno-strict-overflow -fno-ident
-fno-math-errno -fno-strict-aliasing -fstack-protector -Wno-unknown-pragmas
-Wno-address -Wno-parentheses -Wno-sign-compare -Wno-stringop-overflow
-Wno-stringop-overread -Wno-psabi -Wno-multichar -Wno-format-zero-length
-fno-unwind-tables -fno-asynchronous-unwind-tables -fPIC -pipe -pthread -m64
-msse3 -fno-omit-frame-pointer -fvisibility=hidden -O2 -fdata-sections
-ffunction-sections -g0 -Wno-unused-variable -isystem/usr/include/nspr
-isystem/usr/include/nss -isystem/usr/include/webp -DLIBXML_STATIC=
-Wno-narrowing -Wno-class-memaccess -Wno-attributes -Wno-class-memaccess
-Wno-subobject-linkage -Wno-invalid-offsetof -Wno-return-type
-Wno-deprecated-copy -Wno-invalid-offsetof -Wno-changes-meaning
-Wno-deprecated-copy -Wno-expansion-to-defined -std=gnu++20 -fno-exceptions
-fno-rtti -fvisibility-inlines-hidden -c
gen/third_party/blink/renderer/core/core_probes_impl.cc -o
obj/third_party/blink/renderer/core/probe/instrumentation_probes/core_probes_impl.o
gen/third_party/blink/renderer/core/core_probes_impl.cc:3253:1: internal
compiler error: Segmentation fault
3253 | } // namespace blink
| ^
0x736444e45f5f ???
./signal/../sysdeps/unix/sysv/linux/x86_64/libc_sigaction.c:0
0x736444e2a574 __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
0x736444e2a627 __libc_start_main_impl
../csu/libc-start.c:360
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <file:///usr/share/doc/gcc-15/README.Bugs> for instructions.
To replicate
=============
Below is my pseudo code style instruction guide on how to.... (# lines are
comments or commands I didn't use).
I had to install a few extra apt packages to get the build to work on
my setup. I used "~/Downloads" folder for doing the build in (13GB free).
You can download the WebEngine source via Qt Maintenance app or direct
from the Qt website listed below.
Using Qt Maintenance tool, in Extensions, install the source for WebEngine, the
source ends up in "/opt/Qt/6.11.1/Src/qtwebengine"
or... better method, download "qtwebengine-everywhere-src-6.11.1.zip" from -->
https://download.qt.io/official_releases/qt/6.11/6.11.1/submodules/
I used this URL of building WebEngine as basis for my following instructions
-->
https://github.com/OpenBoard-org/OpenBoard/wiki/Build-Qt-WebEngine-on-Ubuntu
# To set up Qt WebEngine build environment
==========================================
sudo apt install -y ccache
# Update symlinks,
https://askubuntu.com/questions/470545/how-do-i-set-up-ccache
sudo /usr/sbin/update-ccache-symlinks
Then add the following text into "~/.profile" -->
# prepend cache if package ccache was installed
if [ -d "/usr/lib/ccache" ] ; then
PATH="/usr/lib/ccache:$PATH"
fi
# You make need to add other packages for your system to successfully configure
the build later on via qt-configure-module.
sudo apt install gperf
sudo apt install python3-html5lib
sudo apt install libnss3-dev
sudo apt-get install qt6-declarative-dev qt6-svg-dev qt6-base-private-dev
qt6-declarative-private-dev
sudo apt install nodejs
To build
=========
extract the "qtwebengine-everywhere-src-6.11.1.zip" file.
open a terminal window
cd ~/Downloads/qtwebengine-everywhere-src-6.11.1
mkdir build
cd build
/opt/Qt/6.11.1/gcc_64/bin/qt-configure-module .. -webengine-proprietary-codecs
cmake --build . --parallel
#build fails with g++ internal seg fault.
