diff --git a/NuttX b/NuttX
index e40af7e82c..af5d2b058c 160000
--- a/NuttX
+++ b/NuttX
@@ -1 +1 @@
-Subproject commit e40af7e82cfb382244fa5f7445db1b00371f6bf1
+Subproject commit af5d2b058c55431607aa5aa29fc1d1bbc7e51089
diff --git a/src/platforms/px4_defines.h b/src/platforms/px4_defines.h
index b41dc7b0eb..8300e1e99b 100644
--- a/src/platforms/px4_defines.h
+++ b/src/platforms/px4_defines.h
@@ -95,13 +95,6 @@ typedef param_t px4_param_t;
 
 #define PX4_ROOTFSDIR
 
-/* XXX this is a hack to resolve conflicts with NuttX headers */
-#if !defined(__PX4_TESTS)
-#define isspace(c) \
-	((c) == ' '  || (c) == '\t' || (c) == '\n' || \
-	 (c) == '\r' || (c) == '\f' || c== '\v')
-#endif
-
 #define _PX4_IOC(x,y) _IOC(x,y)
 
 #define px4_statfs_buf_f_bavail_t int