fix gcc build

src/kernel/ally.c

@@ -12,6 +12,7 @@
 
 #include <util/attrib.h>
 #include <assert.h>
+#include <string.h>
 #include <stdlib.h>
 
 ally * ally_find(ally *al, const struct faction *f) {

src/kernel/ally.h

@@ -24,6 +24,9 @@ extern "C" {
 #endif
 
     struct attrib_type;
+    struct plane;
+    struct faction;
+    struct unit;
     extern struct attrib_type at_npcfaction;
 
     typedef struct ally {

src/kernel/unit.c

@@ -64,6 +64,7 @@ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 /* libc includes */
 #include <assert.h>
+#include <ctype.h>
 #include <limits.h>
 #include <stdlib.h>
 #include <string.h>