#16150: Data races in itimer_thread_func reported by ThreadSanitizer -------------------------------------+------------------------------------- Reporter: gnezdo | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Runtime | Version: 8.4.4 System | Keywords: | Operating System: Linux Architecture: x86_64 | Type of failure: Incorrect result (amd64) | at runtime Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Our local environment allows running Haskell programs under ThreadSanitizer. Even though the GHC runtime and compiled Haskell code are not instrumented, ThreadSanitizer still found a bug through interceptor instrumentation. I'll try to minimize the case and create a reproducer, but in case somebody wants to look at this with just the report, here it is (mildly massaged to remove irrelevant addresses): {{{ ================== WARNING: ThreadSanitizer: data race (pid=2367) Write of size 1 at 0x55986a3e4f10 by thread T1: #0 pthread_mutex_destroy llvm/compiler- rt/lib/tsan/rtl/tsan_interceptors.cc:1245:3 #1 itimer_thread_func vendor_src/v8_4_4/rts/posix/itimer/Pthread.c:152:5 Previous atomic read of size 1 at 0x55986a3e4f10 by main thread: #0 pthread_mutex_lock llvm/compiler- rt/lib/sanitizer_common/sanitizer_common_interceptors.inc:4097:3 #1 startTicker vendor_src/v8_4_4/rts/posix/itimer/Pthread.c:184:5 #2 exitTicker vendor_src/v8_4_4/rts/posix/itimer/Pthread.c:206 #3 __libc_start_main <null> (libc.so.6+0x38bbc) Location is global 'mutex' of size 40 at 0x55986a3e4f10 Thread T1 'ghc_ticker' (tid=2369, running) created by main thread at: #0 pthread_create llvm/compiler- rt/lib/tsan/rtl/tsan_interceptors.cc:980:3 #1 initTicker vendor_src/v8_4_4/rts/posix/itimer/Pthread.c:171:11 #2 __libc_start_main <null> (libc.so.6+0x38bbc) SUMMARY: ThreadSanitizer: data race vendor_src/v8_4_4/rts/posix/itimer/Pthread.c:152:5 in itimer_thread_func ================== ================== WARNING: ThreadSanitizer: data race (pid=2367) Write of size 8 at 0x55986a3e4ee0 by thread T1: #0 pthread_cond_destroy llvm/compiler- rt/lib/tsan/rtl/tsan_interceptors.cc:1216:3 #1 itimer_thread_func vendor_src/v8_4_4/rts/posix/itimer/Pthread.c:153:5 Previous read of size 8 at 0x55986a3e4ee0 by main thread (mutexes: write M146179626018688784): #0 pthread_cond_signal llvm/compiler- rt/lib/tsan/rtl/tsan_interceptors.cc:1202:3 #1 signalCondition vendor_src/v8_4_4/rts/posix/OSThreads.c:111:11 #2 __libc_start_main <null> (libc.so.6+0x38bbc) Location is global 'start_cond' of size 48 at 0x55986a3e4ee0 Mutex M146179626018688784 is already destroyed. Thread T1 'ghc_ticker' (tid=2369, running) created by main thread at: #0 pthread_create llvm/compiler- rt/lib/tsan/rtl/tsan_interceptors.cc:980:3 #1 initTicker vendor_src/v8_4_4/rts/posix/itimer/Pthread.c:171:11 #2 __libc_start_main <null> (libc.so.6+0x38bbc) SUMMARY: ThreadSanitizer: data race vendor_src/v8_4_4/rts/posix/itimer/Pthread.c:153:5 in itimer_thread_func ================== ThreadSanitizer: reported 2 warnings }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/16150 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler