deadlock with dl_iterate_phdr

[YanaiEliyahu]

Regarding the stacktraces below, does it look to you like a deadlock with tcmalloc?
See that in the first I call dl_iterate_phdr and which in its turn calls tcmalloc and then tcmalloc locks a mutex/futex, and the second thread calls tcmalloc (probably inlined the malloc function?), and proceeds to the same function (dl_iterate_phdr) I called in the first thread.
I think the second thread also locks because it's also in tcmalloc::CentralFreeList::Populate.
The last stacktrace of each thread is of functions inside the original project (irrelevant to tcmalloc).

Thread 1 (Thread 0x7f1680ec7000 (LWP 123804)):
#0 0x00007f16b1f6715b in sys_futex (v3=0, a2=0x0, t=0x7ffc5bb09f40, v=2, o=128,
a=0x7f16ad46be48 tcmalloc::Static::pageheap_lock_) at ./src/base/linux_syscall_support.h:2485
#1 base::internal::SpinLockDelay (w=0x7f16ad46be48 tcmalloc::Static::pageheap_lock_, value=2,
loop=) at ./src/base/spinlock_linux-inl.h:84
#2 0x00007f16b1f67074 in SpinLock::SlowLock (this=0x7f16ad46be48 tcmalloc::Static::pageheap_lock_)
at src/base/spinlock.cc:119
#3 0x00007f16ad0a31d8 in Lock (this=) at src/base/spinlock.h:71
#4 SpinLockHolder (l=, this=) at src/base/spinlock.h:133
#5 tcmalloc::CentralFreeList::Populate (
this=this@entry=0x7f16ad45e380 tcmalloc::Static::central_cache_+64448)
at src/central_freelist.cc:328
#6 0x00007f16ad0a32d8 in tcmalloc::CentralFreeList::FetchFromOneSpansSafe (
this=0x7f16ad45e380 tcmalloc::Static::central_cache_+64448, N=4, start=0x7ffc5bb0a070,
end=0x7ffc5bb0a078) at src/central_freelist.cc:284
#7 0x00007f16ad0a3364 in tcmalloc::CentralFreeList::RemoveRange (
this=0x7f16ad45e380 tcmalloc::Static::central_cache_+64448, start=start@entry=0x7ffc5bb0a070,
end=end@entry=0x7ffc5bb0a078, N=4) at src/central_freelist.cc:264
#8 0x00007f16ad0a6b50 in tcmalloc::ThreadCache::FetchFromCentralCache (this=0x883c40, cl=53,
byte_size=16384, oom_handler=0x7f16ad0b45c0 <tcmalloc::cpp_throw_oom(unsigned long)>)
at src/thread_cache.cc:126
#9 0x00007f16a688f49d in void std::vector<scale::details::shared_library_address_space, std::allocatorscale::details::shared_library_address_space >::_M_emplace_back_auxscale::details::shared_library_address_space(scale::details::shared_library_address_space&&) ()
from /home/test_user/sqream-with-submodules/sqream/build/libbasic.so
#10 0x00007f16a68638eb in ?? () from /home/test_user/sqream-with-submodules/sqream/build/libbasic.so
#11 0x00007f1696e381bc in dl_iterate_phdr () from /lib64/libc.so.6
#12 0x00007f16a68602eb in scale::details::library_addresses() ()
...

Thread 3 (Thread 0x7f165d745700 (LWP 123862)):
#0 0x00007f16ace7154d in __lll_lock_wait () from /lib64/libpthread.so.0
#1 0x00007f16ace6ceb6 in _L_lock_941 () from /lib64/libpthread.so.0
#2 0x00007f16ace6cdaf in pthread_mutex_lock () from /lib64/libpthread.so.0
#3 0x00007f1696e380ff in dl_iterate_phdr () from /lib64/libc.so.6
#4 0x00007f16970db083 in _Unwind_Find_FDE (
pc=0x7f16ad0a5132 <tcmalloc::PageHeap::New(unsigned long)+146>, bases=bases@entry=0x7f165d744118)
at ../.././libgcc/unwind-dw2-fde-dip.c:459
#5 0x00007f16970d7a46 in uw_frame_state_for (context=context@entry=0x7f165d744070,
fs=fs@entry=0x7f165d744160) at ../.././libgcc/unwind-dw2.c:1241
#6 0x00007f16970d9598 in _Unwind_Backtrace (
trace=trace@entry=0x7f16b1f65e70 <libgcc_backtrace_helper(_Unwind_Context*, void*)>,
trace_argument=trace_argument@entry=0x7f165d744320) at ../.././libgcc/unwind.inc:290
#7 0x00007f16b1f65c8a in GetStackTrace_libgcc (result=, max_depth=,
skip_count=) at src/stacktrace_libgcc-inl.h:100
#8 0x00007f16b1f66364 in GetStackTrace (result=0x843538, max_depth=30, skip_count=3)
at src/stacktrace.cc:295
#9 0x00007f16ad0a4e36 in RecordGrowth (growth=1048576) at src/page_heap.cc:618
#10 tcmalloc::PageHeap::GrowHeap (this=0x7f16ad2cb640 tcmalloc::Static::pageheap_, n=)
at src/page_heap.cc:644
#11 0x00007f16ad0a5133 in tcmalloc::PageHeap::New (this=0x7f16ad2cb640 tcmalloc::Static::pageheap_,
n=n@entry=5) at src/page_heap.cc:154
#12 0x00007f16ad0a30d5 in tcmalloc::CentralFreeList::Populate (
this=this@entry=0x7f16ad45e840 tcmalloc::Static::central_cache_+65664)
at src/central_freelist.cc:329
#13 0x00007f16ad0a32d8 in tcmalloc::CentralFreeList::FetchFromOneSpansSafe (
this=0x7f16ad45e840 tcmalloc::Static::central_cache_+65664, N=1, start=0x7f165d7444c0,
end=0x7f165d7444c8) at src/central_freelist.cc:284
#14 0x00007f16ad0a3364 in tcmalloc::CentralFreeList::RemoveRange (
this=0x7f16ad45e840 tcmalloc::Static::central_cache_+65664, start=start@entry=0x7f165d7444c0,
end=end@entry=0x7f165d7444c8, N=1) at src/central_freelist.cc:264
#15 0x00007f16ad0a6b50 in tcmalloc::ThreadCache::FetchFromCentralCache (this=0x887980, cl=54,
byte_size=20480, oom_handler=0x7f16ad0b45c0 <tcmalloc::cpp_throw_oom(unsigned long)>)
at src/thread_cache.cc:126
#16 0x00007f16a68e498c in set_status(status_information const&) ()
...

[ckennelly]

I believe this bug report may apply to https://github.com/gperftools/gperftools, not this project.