On Wed, Dec 31, 2008 at 10:44:07PM -0800, Donn Cave wrote:
I tried to build GHC 6.10.1 on NetBSD 4.0 this afternoon, and ran into an error, where cabal-bin calls the stage2 ghc in utils/installPackage.
pthread_mutex_unlock() is called, evidently from fileLock(), with an invalid mutex.
NetBSD's pthread implementation differs from Linux in its intolerance of such things. I have found errors where someone forgets that a mutex was never used and tries to unlock it. I guess you could do that all day long on Linux without noticing anything, but NetBSD aborts the program. In the present case, I don't see anything like that wrong in rts/FileLock.c, though. I'm stumped.
So I'm checking, has anyone else built 6.10 on NetBSD?
Only on OpenBSD, and there it builds fine (when bootstrapping from either ghc-6.6 or -6.10). But what's interesting is that in includes/OSThreads.h the return values of pthread_mutex_lock(3) and pthread_mutex_unlock(3) aren't checked except apparently on Linux when building with DEBUG defined. You could either try to build with LOCK_DEBUG defined, so you see exactly when a lock is acquired and released, or try to build with DEBUG defined and that `&& defined(linux_HOST_OS)' removed from OSThreads.h to see what's going wrong. BTW: is there any pthread implementation still in the wild where pthread_mutex_{,un}lock() does NOT indicate a deadlock by EDEADLK? If not, the DEBUG part of OSThreads.h could be used for all systems, not only Linux. Ciao, Kili -- A typo a day, keeps the dictionnary away. -- Miod Vallat