diff --git a/Tools/ardupilotwaf/boards.py b/Tools/ardupilotwaf/boards.py
index f00cf05fae..6d912b7477 100644
--- a/Tools/ardupilotwaf/boards.py
+++ b/Tools/ardupilotwaf/boards.py
@@ -423,6 +423,7 @@ class px4(Board):
 
         env.DEFINES.update(
             CONFIG_HAL_BOARD = 'HAL_BOARD_PX4',
+            HAVE_OCLOEXEC = 0,
             HAVE_STD_NULLPTR_T = 0,
         )
         env.CXXFLAGS += [
diff --git a/mk/px4_targets.mk b/mk/px4_targets.mk
index f2ed1a1773..494a98b024 100644
--- a/mk/px4_targets.mk
+++ b/mk/px4_targets.mk
@@ -34,6 +34,7 @@ EXTRAFLAGS += -D__STDC_FORMAT_MACROS
 EXTRAFLAGS += -DHAVE_STD_NULLPTR_T=0
 EXTRAFLAGS += -DHAVE_ENDIAN_H=0
 EXTRAFLAGS += -DHAVE_BYTESWAP_H=0
+EXTRAFLAGS += -DHAVE_OCLOEXEC=0
 
 EXTRAFLAGS += -I$(BUILDROOT)/libraries/GCS_MAVLink/include/mavlink
 
diff --git a/mk/vrbrain_targets.mk b/mk/vrbrain_targets.mk
index ff1667728d..bbd286798a 100644
--- a/mk/vrbrain_targets.mk
+++ b/mk/vrbrain_targets.mk
@@ -42,6 +42,7 @@ EXTRAFLAGS += -DUAVCAN=1
 
 # Add missing parts from libc and libstdc++
 EXTRAFLAGS += -DHAVE_STD_NULLPTR_T=0
+EXTRAFLAGS += -DHAVE_OCLOEXEC=0
 
 EXTRAFLAGS += -I$(BUILDROOT)/libraries/GCS_MAVLink/include/mavlink