Include pthread.h.  Comment MIR_NO_PARALLEL_GEN definition.
@@ -31,7 +31,10 @@ static inline int mir_assert (int cond) { return 0 && cond; }
#define MIR_NO_SCAN 0
#endif
-#define MIR_NO_PARALLEL_GEN 1
+//#define MIR_NO_PARALLEL_GEN 1
+#ifndef MIR_NO_PARALLEL_GEN
+#include <pthread.h>
+#endif
#ifdef __GNUC__
#define MIR_UNUSED __attribute__ ((unused))
