diff options
authorRich Felker <>2011-09-04 21:37:07 -0400
committerRich Felker <>2011-09-04 21:37:07 -0400
commita7778dae226fbae335383bc92b6cdfccc5ea9f2e (patch)
parent22e4542348352235614b57948025bdd0cc30dc32 (diff)
handle pending cancellation when enabling async cancellation
this is not strictly required by the standard, but without it, there is a race condition where cancellation arriving just before async cancellation is enabled might not be acted upon. it is impossible for a conforming application to work around this race condition since calling pthread_testcancel after setting async cancellation mode is not allowed (pthread_testcancel is not specified to be async-cancel-safe). thus the implementation should be responsible for eliminating the race, from a quality-of-implementation standpoint.
1 files changed, 1 insertions, 0 deletions
diff --git a/src/thread/pthread_setcanceltype.c b/src/thread/pthread_setcanceltype.c
index 7eb543a8..ce2fff07 100644
--- a/src/thread/pthread_setcanceltype.c
+++ b/src/thread/pthread_setcanceltype.c
@@ -6,5 +6,6 @@ int pthread_setcanceltype(int new, int *old)
if (new > 1U) return EINVAL;
if (old) *old = self->cancelasync;
self->cancelasync = new;
+ if (new) pthread_testcancel();
return 0;