diff --git a/src/i830_bios.c b/src/i830_bios.c
index 556f57b3..14e354ed 100644
--- a/src/i830_bios.c
+++ b/src/i830_bios.c
@@ -29,6 +29,9 @@
 #undef VERSION	/* XXX edid.h has a VERSION too */
 #endif
 
+#include <stdio.h>
+#include <string.h>
+
 #define _PARSE_EDID_
 #include "xf86.h"
 #include "i830.h"
diff --git a/src/i830_display.c b/src/i830_display.c
index 2fb918a3..ef7e8322 100644
--- a/src/i830_display.c
+++ b/src/i830_display.c
@@ -31,6 +31,10 @@
 #endif
 
 #include <unistd.h>
+#include <string.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <math.h>
 
 #include "xf86.h"
 #include "i830.h"
diff --git a/src/i830_sdvo.c b/src/i830_sdvo.c
index cbc9c6b0..c7625419 100644
--- a/src/i830_sdvo.c
+++ b/src/i830_sdvo.c
@@ -26,6 +26,9 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
+
+#include <string.h>
+
 #include "xf86.h"
 #include "xf86_OSproc.h"
 #include "compiler.h"