diff --git a/src/ai.c b/src/ai.c
index 26c0927..9588a0f 100644
--- a/src/ai.c
+++ b/src/ai.c
@@ -1,3 +1,7 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
 #include "lauxlib.h"
 #include "lualib.h"
 
diff --git a/src/conf.c b/src/conf.c
index 8a334d0..d704015 100644
--- a/src/conf.c
+++ b/src/conf.c
@@ -1,3 +1,4 @@
+#include <stdlib.h>
 #include <unistd.h>
 #include <string.h>
 #include <getopt.h>
diff --git a/src/land.c b/src/land.c
index e2c4510..5fe5de4 100644
--- a/src/land.c
+++ b/src/land.c
@@ -1,3 +1,8 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+
 #include "lephisto.h"
 #include "log.h"
 #include "toolkit.h"
diff --git a/src/misn_lua.c b/src/misn_lua.c
index ef18d60..d9110a1 100644
--- a/src/misn_lua.c
+++ b/src/misn_lua.c
@@ -1,3 +1,8 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+
 #include "lua.h"
 #include "lauxlib.h"
 
diff --git a/src/opengl.c b/src/opengl.c
index 7f08b07..5759c3f 100644
--- a/src/opengl.c
+++ b/src/opengl.c
@@ -4,9 +4,10 @@
 #include <ft2build.h>
 #include <freetype/freetype.h>
 #include <freetype/ftglyph.h>
-#include <math.h>
-#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
 #include <string.h>
+#include <stdarg.h>
 
 #include "lephisto.h"
 #include "log.h"
diff --git a/src/physics.c b/src/physics.c
index ee6050b..3899eea 100644
--- a/src/physics.c
+++ b/src/physics.c
@@ -1,5 +1,6 @@
-#include <math.h>
 #include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
 
 #include "lephisto.h"
 #include "log.h"
diff --git a/src/toolkit.c b/src/toolkit.c
index 6f43e75..b73fcac 100644
--- a/src/toolkit.c
+++ b/src/toolkit.c
@@ -1,3 +1,5 @@
+#include <stdarg.h>
+
 #include "lephisto.h"
 #include "log.h"
 #include "pause.h"