Boost threads coring on startup.

Question

I have a program that brings up and tears down multiple threads throughout its life. Everything works great for awhile, but eventually, I get the following core dump stack trace.

#0  0x009887a2 in _dl_sysinfo_int80 () from /lib/ld-linux.so.2
#1  0x007617a5 in raise () from /lib/tls/libc.so.6
#2  0x00763209 in abort () from /lib/tls/libc.so.6
#3  0x003ec1bb in __gnu_cxx::__verbose_terminate_handler () from /usr/lib/libstdc++.so.6
#4  0x003e9ed1 in __cxa_call_unexpected () from /usr/lib/libstdc++.so.6
#5  0x003e9f06 in std::terminate () from /usr/lib/libstdc++.so.6
#6  0x003ea04f in __cxa_throw () from /usr/lib/libstdc++.so.6
#7  0x00d5562b in boost::thread::start_thread () from /h/Program/bin/../lib/libboost_thread-gcc34-mt-1_39.so.1.39.0

At first, I was leaking threads, and figured the core was due to hitting some maximum limit of number of current threads, but now it seems that this problems occurs even when I don't. For reference, in the core above there were 13 active threads executing.

I did some searching to try and figure out why start_thread would core, but I didn't come across anything. Anyone have any ideas?

Answer 1

start_thread is throwing an uncaught exception, see which exceptions can start_thread throw and place a catch around it to see what is the problem.

Answer 2

What are the values carried by thread_resource_error? It looks like you can call native_error() to find out.

Since this is a wrapper around pthreads there are only a couple of possibilities - EAGAIN, EINVAL and EPERM. It looks as if boost has exceptions it would likely throw for EINVAL and EPERM - i.e. unsupported_thread_option() and thread_permission_error().

That pretty much leaves EAGAIN so I would double check that you really aren't exceeding the system limits on the number of threads. You are sure you are joining them, or if detached, they are really gone?