fix build with both simgrid and leveldb

include/starpu_thread.h

@@ -18,6 +18,11 @@
 #ifndef __STARPU_THREAD_H__
 #define __STARPU_THREAD_H__
 
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
 #ifdef STARPU_SIMGRID
 #include <xbt/synchro_core.h>
 #include <msg/msg.h>
@@ -25,11 +30,6 @@
 #include <pthread.h>
 #endif
 
-#ifdef __cplusplus
-extern "C"
-{
-#endif
-
 /*
  * Encapsulation of the pthread_create function.
  */