[PATCH] D29994: Use pthreads for thread-local lsan allocator cache on darwin

[Francis Ricci via Phabricator via llvm-commits]

fjricci added a comment.

The stack trace from the debugger isn't particularly helpful:

   thread #2, name = 'stack-use-after', stop reason = signal SIGSEGV: address access protected (fault address: 0x7ffff7e72020)
    frame #0: stack-use-after-return.cc.tmp`Func1() at stack-use-after-return.cc:39
     36  	}
     37  	
     38  	__attribute__((noinline))
  -> 39  	char *Func1() {
     40  	  char local[kSize];
     41  	  return Ident(local);
     42  	}
  (lldb) bt all
    thread #1, name = 'stack-use-after'
      frame #0: libpthread.so.0`pthread_join(threadid=140737352574720, thread_return=0x0000000000000000) at pthread_join.c:92
      frame #1: stack-use-after-return.cc.tmp`main at stack-use-after-return.cc:74
      frame #2: libc.so.6`__libc_start_main(main=(stack-use-after-return.cc.tmp`main), argc=1, argv=0x00007fffffffdb78, init=<unavailable>, fini=<unavailable>, rtld_fini=<unavailable>, stack_end=0x00007fffffffdb68) at libc-start.c:287
      frame #3: 0x000000000041ba7c stack-use-after-return.cc.tmp`_start + 41
  * thread #2, name = 'stack-use-after', stop reason = signal SIGSEGV: address access protected (fault address: 0x7ffff7e72020)
    * frame #0: stack-use-after-return.cc.tmp`Func1() at stack-use-after-return.cc:39
      frame #1: stack-use-after-return.cc.tmp`Thread(void*) at stack-use-after-return.cc:61
      frame #2: libpthread.so.0`start_thread(arg=0x00007ffff7e82700) at pthread_create.c:312
      frame #3: libc.so.6`__clone at clone.S:111

The crash error also goes away if I add a CHECK(0); to GetAllocatorCache(), which is similarly strange.


Repository:
  rL LLVM

https://reviews.llvm.org/D29994