diff options
| -rw-r--r-- | rts/RaiseAsync.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/rts/RaiseAsync.c b/rts/RaiseAsync.c index c14b4112bd..9e5a8c3b2f 100644 --- a/rts/RaiseAsync.c +++ b/rts/RaiseAsync.c @@ -156,8 +156,7 @@ throwTo (Capability *cap, // the Capability we hold MessageThrowTo *msg; msg = (MessageThrowTo *) allocate(cap, sizeofW(MessageThrowTo)); - // message starts locked; the caller has to unlock it when it is - // ready. + // the message starts locked; see below SET_HDR(msg, &stg_WHITEHOLE_info, CCS_SYSTEM); msg->source = source; msg->target = target; @@ -166,9 +165,16 @@ throwTo (Capability *cap, // the Capability we hold switch (throwToMsg(cap, msg)) { case THROWTO_SUCCESS: + // unlock the message now, otherwise we leave a WHITEHOLE in + // the heap (#6103) + SET_HDR(msg, &stg_MSG_THROWTO_info, CCS_SYSTEM); return NULL; + case THROWTO_BLOCKED: default: + // the caller will unlock the message when it is ready. We + // cannot unlock it yet, because the calling thread will need + // to tidy up its state first. return msg; } } |