title: AIX: Why does throwing an exception abort multithreaded code?
body: <p>We get an abort when a C++ exception is thrown when running code compiled with -pthread.</p>
  
  <p>Platform: AIX 5.3 technical level 8
  Compiler: gcc 3.4.6
  Linker: AIX linker 1.65.2.4</p>
  
  <p>Test Code:</p>
  
  <pre><code>// exception.cpp
  #include &lt;iostream&gt;
  
  class MyException
  {
  public:
          MyException(){}
          virtual ~MyException(){};
  };
  
  void gTest()
  {
          throw MyException();
  }
  
  int main()
  {
          try
          {
                  gTest();
          }
          catch(MyException const &amp; ex)
          {
                  std::cout &lt;&lt; "exception was caught" &lt;&lt; std::endl;
          }
  
          return 0;
  }
  
  
  $ g++ exception.cpp
  $ ./a.out
  exception was caught
  $ g++ -pthread exception.cpp
  $ ./a.out
  terminate called after throwing an instance of 'MyException'
  IOT/Abort trap (core dumped)
  $ gdb a.out
  GNU gdb 6.0
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  This GDB was configured as "powerpc-ibm-aix5.1.0.0"...
  (gdb) run
  Starting program: /home/leeder/except/a.out
  terminate called after throwing an instance of 'MyException'
  
  Program received signal SIGABRT, Aborted.
  Switching to Thread 1
  0xd0124834 in pthread_kill () from /usr/lib/libpthreads.a(shr_xpg5.o)
  (gdb) bt
  #0 0xd0124834 in pthread_kill () from /usr/lib/libpthreads.a(shr_xpg5.o)
  #1 0xd01242a8 in _p_raise () from /usr/lib/libpthreads.a(shr_xpg5.o)
  #2 0xd0359bdc in raise () from /usr/lib/libc.a(shr.o)
  #3 0xd03b7efc in abort () from /usr/lib/libc.a(shr.o)
  #4 0xd0ca1800 in __gnu_cxx::__verbose_terminate_handler() () at ../../.././libstdc++-v3/libsupc++/vterminate.cc:96
  #5 0xd0ca1220 in __cxxabiv1::__terminate(void (*)()) (handler=0)
  at ../../.././libstdc++-v3/libsupc++/eh_terminate.cc:43
  #6 0xd0ca128c in std::terminate() () at ../../.././libstdc++-v3/libsupc++/eh_terminate.cc:53
  #7 0xd0ca7cfc in __cxa_throw (obj=0x200084e8, tinfo=0xffffffff, dest=Cannot access memory at address 0xffffffff
  )
  at ../../.././libstdc++-v3/libsupc++/eh_throw.cc:80
  #8 0x100008dc in gTest() ()
  #9 0x100009f0 in main ()
  (gdb)
  </code></pre>
  
  <p>Has anyone seen anything similar?</p>
  
  <p>Do you think upgrading to gcc 4 would help?</p>
  
  <p>What about switching to IBM's xl compiler?</p>
  
  <p>Thanks.</p>