QtCreator executes external processes at start-up

statx(AT_FDCWD, "/usr/libexec/python3-sphinx/custom-clang", AT_STATX_SYNC_AS_STAT, STATX_ALL, 0x7ffc4dca2550) = -1 ENOENT (No such file or directory)
statx(AT_FDCWD, "/usr/share/Modules/bin/custom-clang", AT_STATX_SYNC_AS_STAT, STATX_ALL, 0x7ffc4dca2550) = -1 ENOENT (No such file or directory)
statx(AT_FDCWD, "/usr/local/bin/custom-clang", AT_STATX_SYNC_AS_STAT, STATX_ALL, {stx_mask=STATX_ALL, stx_attributes=0, stx_mode=S_IFREG|0755, stx_size=56, ...}) = 0
access("/usr/local/bin/custom-clang", X_OK) = 0
...
clone(child_stack=NULL, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7fa97ad1fad0) = 15364
...
read(29, "WHY AM I RUN???\n", 16)       = 16
...
read(29, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 65536) = 65536
...
read(29, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 65536) = 65536
...
write(2, "terminate called after throwing "..., 48terminate called after throwing an instance of ') = 48
write(2, "std::bad_alloc", 14std::bad_alloc)          = 14

#0  0x00007ffff669aeb5 in raise () at /lib64/libc.so.6
#1  0x00007ffff6685895 in abort () at /lib64/libc.so.6
#2  0x00007ffff68e06da in  () at /lib64/libstdc++.so.6
#3  0x00007ffff68ec61c in  () at /lib64/libstdc++.so.6
#4  0x00007ffff68ec677 in  () at /lib64/libstdc++.so.6
#5  0x00007ffff68ec8d9 in  () at /lib64/libstdc++.so.6
#6  0x00007ffff6ae5e59 in qTerminate() () at /lib64/libQt5Core.so.5
#7  0x00007ffff6ae8828 in  () at /lib64/libQt5Core.so.5
#8  0x00007ffff6b2a138 in QByteArray::append(QByteArray const&) () at /lib64/libQt5Core.so.5
#9  0x00007ffff7e4d606 in QByteArray::operator+=(QByteArray const&) (a=..., this=0x555556b840b8) at /usr/include/qt5/QtCore/qbytearray.h:593
#10 0x00007ffff7e4d606 in Utils::ChannelBuffer::append(QByteArray const&, bool) (this=0x555556b840a8, text=..., emitSignals=<optimized out>) at synchronousprocess.cpp:245
#11 0x00007ffff7e4d6f0 in Utils::SynchronousProcess::processStdOut(bool) (this=<optimized out>, emitSignals=<optimized out>) at synchronousprocess.cpp:627
#12 0x00007ffff6ced6f0 in QMetaObject::activate(QObject*, int, int, void**) () at /lib64/libQt5Core.so.5
#13 0x00007ffff6c4e8de in QProcess::readyReadStandardOutput(QProcess::QPrivateSignal) () at /lib64/libQt5Core.so.5
#14 0x00007ffff6c54819 in  () at /lib64/libQt5Core.so.5
#15 0x00007ffff6c5ac50 in  () at /lib64/libQt5Core.so.5
#16 0x00007ffff6c4f231 in QProcess::waitForFinished(int) () at /lib64/libQt5Core.so.5
#17 0x00007ffff7e4e0ef in Utils::SynchronousProcess::runBlocking(QString const&, QStringList const&) (this=this@entry=0x7fffffffc3d0, binary=..., args=...) at synchronousprocess.cpp:516
#18 0x00007fffcb724ea8 in ProjectExplorer::runGcc(Utils::FileName const&, QStringList const&, QStringList const&) (gcc=..., arguments=..., env=...) at gcctoolchain.cpp:91
#19 0x00007fffcb725f6c in ProjectExplorer::gccPredefinedMacros(Utils::FileName const&, QStringList const&, QStringList const&) (gcc=..., args=..., env=...) at gcctoolchain.cpp:108
#20 0x00007fffcb728eb7 in ProjectExplorer::Internal::GccToolChainFactory::autoDetectToolChain(Utils::FileName const&, Core::Id, ProjectExplorer::Abi const&)
    (this=0x555555e1fe10, compilerPath=..., language=..., requiredAbi=...) at gcctoolchain.cpp:992
#21 0x00007fffcb729a02 in ProjectExplorer::Internal::GccToolChainFactory::autoDetectToolchains(Utils::FileName const&, ProjectExplorer::Abi const&, Core::Id, Core::Id, QList<ProjectExplorer::ToolChain*> const&)
    (this=0x555555e1fe10, compilerPath=..., requiredAbi=..., language=..., requiredTypeId=..., alreadyKnown=...) at gcctoolchain.cpp:978
#22 0x00007fffcb72a083 in ProjectExplorer::Internal::GccToolChainFactory::versionProbe(QString const&, Core::Id, Core::Id, QList<ProjectExplorer::ToolChain*>&, QList<ProjectExplorer::ToolChain*>&, QSet<QString> const&) (this=0x555555e1fe10, name=..., language=..., type=..., tcs=..., known=..., filteredNames=...) at gcctoolchain.cpp:892
#23 0x00007fffcb72abad in ProjectExplorer::Internal::ClangToolChainFactory::autoDetect(QList<ProjectExplorer::ToolChain*> const&) (this=0x555555e1fe10, alreadyKnown=...) at /usr/include/qt5/QtCore/qstring.h:687
#24 0x00007fffcb84e8e6 in ProjectExplorer::Internal::autoDetectToolChains (alreadyKnownTcs=...) at toolchainsettingsaccessor.cpp:74
#25 0x00007fffcb84e8e6 in ProjectExplorer::Internal::ToolChainSettingsAccessor::restoreToolChains(QWidget*) const (this=this@entry=0x555555704230, parent=0x555555747450) at toolchainsettingsaccessor.cpp:208
#26 0x00007fffcb84792e in ProjectExplorer::ToolChainManager::restoreToolChains() () at toolchainmanager.cpp:122
#27 0x00007fffcb6e3ee9 in ProjectExplorer::ProjectExplorerPlugin::restoreKits() (this=<optimized out>) at projectexplorer.cpp:1810
#28 0x00007ffff6cf9dc6 in  () at /lib64/libQt5Core.so.5
#29 0x00007ffff6cee3c5 in QObject::event(QEvent*) () at /lib64/libQt5Core.so.5
#30 0x00007ffff77d9ad6 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /lib64/libQt5Widgets.so.5
#31 0x00007ffff77e2f50 in QApplication::notify(QObject*, QEvent*) () at /lib64/libQt5Widgets.so.5
#32 0x00007ffff6cc32e8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /lib64/libQt5Core.so.5
#33 0x00007ffff6d176b3 in QTimerInfoList::activateTimers() () at /lib64/libQt5Core.so.5
#34 0x00007ffff6d17f6c in  () at /lib64/libQt5Core.so.5
#35 0x00007ffff5412fd0 in g_main_context_dispatch () at /lib64/libglib-2.0.so.0
#36 0x00007ffff5413368 in  () at /lib64/libglib-2.0.so.0
#37 0x00007ffff5413413 in g_main_context_iteration () at /lib64/libglib-2.0.so.0
#38 0x00007ffff6d183f5 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#39 0x00007ffff6cc22bb in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#40 0x00007ffff6cc9fd6 in QCoreApplication::exec() () at /lib64/libQt5Core.so.5
#41 0x000055555555fd94 in main(int, char**) (argc=<optimized out>, argv=<optimized out>) at main.cpp:631