--- a/src/lib/cache.c	Sat Oct 04 15:13:56 2014 +0300
+++ b/src/lib/cache.c	Mon Jul 03 23:15:14 2017 +0300
@@ -4,6 +4,7 @@
 #include "error.h"
 
 #include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/stat.h>

--- a/src/lib/image.c	Sat Oct 04 15:13:56 2014 +0300
+++ b/src/lib/image.c	Mon Jul 03 23:15:14 2017 +0300
@@ -8,6 +8,7 @@
 #include "shared/log.h"
 
 #include <stdlib.h>
+#include <string.h>
 #include <sys/stat.h>
 #include <unistd.h>
 #include <errno.h>

--- a/src/lib/png.c	Sat Oct 04 15:13:56 2014 +0300
+++ b/src/lib/png.c	Mon Jul 03 23:15:14 2017 +0300
@@ -3,6 +3,7 @@
 #include "shared/log.h" // debug only
 
 #include <png.h> // sysmtem libpng header
+#include <string.h>
 #include <assert.h>
 
 

--- a/src/lib/tile.c	Sat Oct 04 15:13:56 2014 +0300
+++ b/src/lib/tile.c	Mon Jul 03 23:15:14 2017 +0300
@@ -3,6 +3,7 @@
 #include "shared/log.h" // only FATAL
 
 #include <stdlib.h>
+#include <string.h>
 #include <assert.h>
 
 int pt_tile_mem_write (struct pt_tile_mem *buf, void *data, size_t len)