https://github.com/eXeC64/imv/issues/299
--- a/src/backend_freeimage.c	2020-12-17 15:30:42.000000000 -0500
+++ b/src/backend_freeimage.c	2021-01-23 12:03:46.175921640 -0500
@@ -8,4 +8,5 @@
 #include <FreeImage.h>
 #include <stdlib.h>
+#include <string.h>
 
 struct private {
