diff --git a/libavdevice/bktr.c b/libavdevice/bktr.c
index 7259f5b6235001d98e2af98ea7030bb611d6af84..0ea8dfb02c41034e7c3fa952c918acbbcccd1313 100644
--- a/libavdevice/bktr.c
+++ b/libavdevice/bktr.c
@@ -39,9 +39,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <sys/ioctl.h>
-#ifdef HAVE_SYS_MMAN_H
 #include <sys/mman.h>
-#endif
 #include <sys/time.h>
 #include <signal.h>
 
diff --git a/libavdevice/dv1394.c b/libavdevice/dv1394.c
index 85836f1b80290692e771e8fb1278d434db8efc29..fdf8428b5e8121f732929cc79d8d380ff6f37ba1 100644
--- a/libavdevice/dv1394.c
+++ b/libavdevice/dv1394.c
@@ -24,9 +24,7 @@
 #include <fcntl.h>
 #include <errno.h>
 #include <sys/ioctl.h>
-#ifdef HAVE_SYS_MMAN_H
 #include <sys/mman.h>
-#endif
 #include <sys/poll.h>
 #include <sys/time.h>
 #include <time.h>
diff --git a/libavdevice/v4l.c b/libavdevice/v4l.c
index 75ee6a35a168a83269f99b8954137d84413879df..cc31c27115e3f44394649aea929178b646375e41 100644
--- a/libavdevice/v4l.c
+++ b/libavdevice/v4l.c
@@ -25,9 +25,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <sys/ioctl.h>
-#ifdef HAVE_SYS_MMAN_H
 #include <sys/mman.h>
-#endif
 #include <sys/time.h>
 #define _LINUX_TIME_H 1
 #include <linux/videodev.h>
diff --git a/libavdevice/v4l2.c b/libavdevice/v4l2.c
index ab5e6857cb89badfefe4a82a509759fb89b09783..565fa5253f6ced3220799fa550c4065cbf7d7a13 100644
--- a/libavdevice/v4l2.c
+++ b/libavdevice/v4l2.c
@@ -32,9 +32,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <sys/ioctl.h>
-#ifdef HAVE_SYS_MMAN_H
 #include <sys/mman.h>
-#endif
 #include <sys/time.h>
 #include <asm/types.h>
 #include <linux/videodev2.h>