Define thread primitives if they're supported.

On iOS, we use the pthread-based implementation of Itimer.c even for a
non-threaded RTS. Since 999c464, this relies on synchronization
primitives like Mutex, so ensure those primitives are defined whenever
they are supported, even if !THREADED_RTS.

Fixes #12799.

Reviewers: erikd, austin, simonmar, bgamari

Reviewed By: simonmar, bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2712

GHC Trac Issues: #12799

1 files changed, 19 insertions, 18 deletions

diff --git a/rts/posix/OSThreads.c b/rts/posix/OSThreads.c
index 63e979080c..a52fbe5d37 100644
--- a/rts/posix/OSThreads.c
+++ b/rts/posix/OSThreads.c
@@ -35,7 +35,6 @@
 #endif
 #endif
 
-#if defined(THREADED_RTS)
 #include "RtsUtils.h"
 #include "Task.h"
 
@@ -215,6 +214,8 @@ freeThreadLocalKey (ThreadLocalKey *key)
     }
 }
 
+#if defined(THREADED_RTS)
+
 static void *
 forkOS_createThreadWrapper ( void * entry )
 {
@@ -266,6 +267,23 @@ getNumberOfProcessors (void)
     return nproc;
 }
 
+#else /* !defined(THREADED_RTS) */
+
+int
+forkOS_createThread ( HsStablePtr entry STG_UNUSED )
+{
+    return -1;
+}
+
+void freeThreadingResources (void) { /* nothing */ }
+
+uint32_t getNumberOfProcessors (void)
+{
+    return 1;
+}
+
+#endif /* defined(THREADED_RTS) */
+
 #if defined(HAVE_SCHED_H) && defined(HAVE_SCHED_SETAFFINITY)
 // Schedules the thread to run on CPU n of m.  m may be less than the
 // number of physical CPUs, in which case, the thread will be allowed
@@ -353,23 +371,6 @@ interruptOSThread (OSThreadId id)
     pthread_kill(id, SIGPIPE);
 }
 
-#else /* !defined(THREADED_RTS) */
-
-int
-forkOS_createThread ( HsStablePtr entry STG_UNUSED )
-{
-    return -1;
-}
-
-void freeThreadingResources (void) { /* nothing */ }
-
-uint32_t getNumberOfProcessors (void)
-{
-    return 1;
-}
-
-#endif /* defined(THREADED_RTS) */
-
 KernelThreadId kernelThreadId (void)
 {
 #if defined(linux_HOST_OS)