$OpenBSD$
Index: threads.c
--- threads.c.orig
+++ threads.c
@@ -44,13 +44,15 @@
 #undef MAX_CPUS
 #define MAX_CPUS CPU_MAXSIZE
 
-#elif defined(TARGET_OS_SOLARIS)
+#elif defined(TARGET_OS_SOLARIS) || defined(TARGET_OS_OPENBSD)
 #include <string.h>
 #include <unistd.h>
 #include <errno.h>
 #include <sys/types.h>
+#if defined(TARGET_OS_SOLARIS)
 #include <sys/processor.h>
 #include <sys/procset.h>
+#endif
 
 
 #elif defined(TARGET_OS_MACOSX)
@@ -111,7 +113,7 @@ uint32_t thread_count_native(struct cpuid_state_t *sta
 		return 1;
 
 	return count;
-#elif defined(TARGET_OS_SOLARIS)
+#elif defined(TARGET_OS_SOLARIS) || defined(TARGET_OS_OPENBSD)
 	long count;
 
 	if ((count = sysconf(_SC_NPROCESSORS_ONLN)) == -1)
@@ -263,7 +265,8 @@ int thread_bind_native(__unused_variable struct cpuid_
 
 	return ret == 0 ? 0 : 1;
 #else
-#error "thread_bind_native() not defined for this platform"
+#warning "thread_bind_native() not defined for this platform"
+	return 0;
 #endif
 }