root@crow:~ # gdb --pid 98922
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Attaching to process 98922
Reading symbols from /usr/obj/root/head/powerpc.powerpc64/tmp/usr/bin/ld.lld...
(No debugging symbols found in /usr/obj/root/head/powerpc.powerpc64/tmp/usr/bin/ld.lld)
[New LWP 100734 of process 98922]
[New LWP 100752 of process 98922]
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[Switching to LWP 101221 of process 98922]
0x0000000011bb2d50 in _umtx_op_err ()
(gdb) bt
#0  0x0000000011bb2d50 in _umtx_op_err ()
#1  0x0000000011b9f1b4 in _thr_umtx_timedwait_uint ()
#2  0x0000000011baefd0 in cond_wait_common ()
#3  0x0000000011c05c40 in std::__1::condition_variable::wait(std::__1::unique_lock<std::__1::mutex>&) ()
#4  0x00000000104cc5c4 in llvm::parallel::detail::TaskGroup::~TaskGroup() ()
#5  0x00000000103106a0 in void llvm::parallel::detail::parallel_for_each_n<unsigned long, llvm::function_ref<void (unsigned long)> >(unsigned long, unsigned long, llvm::function_ref<void (unsigned long)>) ()
#6  0x0000000010401828 in lld::elf::MergeNoTailSection::finalizeContents() ()
#7  0x0000000010401e68 in lld::elf::mergeSections() ()
#8  0x00000000102f630c in void lld::elf::LinkerDriver::link<llvm::object::ELFType<(llvm::support::endianness)0, true> >(llvm::opt::InputArgList&) ()
#9  0x00000000102e9794 in lld::elf::LinkerDriver::main(llvm::ArrayRef<char const*>) ()
#10 0x00000000102e7bc4 in lld::elf::link(llvm::ArrayRef<char const*>, bool, llvm::raw_ostream&) ()
#11 0x00000000104b6b90 in main ()
(gdb) disassemble
Dump of assembler code for function _umtx_op_err:
   0x0000000011bb2d40 <+0>:	addis   r2,r12,35
   0x0000000011bb2d44 <+4>:	addi    r2,r2,-30264
   0x0000000011bb2d48 <+8>:	li      r0,454
   0x0000000011bb2d4c <+12>:	sc      
=> 0x0000000011bb2d50 <+16>:	blr
   0x0000000011bb2d54 <+20>:	.long 0x0
   0x0000000011bb2d58 <+24>:	.long 0x0
   0x0000000011bb2d5c <+28>:	.long 0x0
End of assembler dump.
(gdb)