diff --git a/libgphoto2/gphoto2-file.c b/libgphoto2/gphoto2-file.c
index 23659c988..00e328625 100644
--- a/libgphoto2/gphoto2-file.c
+++ b/libgphoto2/gphoto2-file.c
@@ -200,7 +200,7 @@ gp_file_append (CameraFile *file, const char *data,
 			t = realloc (file->data, sizeof (char) * (file->size + size));
 			if (!t)
 				return GP_ERROR_NO_MEMORY;
-			file->data = t;
+			file->data = (unsigned char*)t;
 		}
 		memcpy (&file->data[file->size], data, size);
 		file->size += size;
@@ -294,7 +294,7 @@ gp_file_set_data_and_size (CameraFile *file, char *data,
 	case GP_FILE_ACCESSTYPE_MEMORY:
 		if (file->data)
 			free (file->data);
-		file->data = data;
+		file->data = (unsigned char*)data;
 		file->size = size;
 		break;
 	case GP_FILE_ACCESSTYPE_FD: {
@@ -358,7 +358,7 @@ gp_file_get_data_and_size (CameraFile *file, const char **data,
 	switch (file->accesstype) {
 	case GP_FILE_ACCESSTYPE_MEMORY:
 		if (data)
-			*data = file->data;
+			*data = (char*)file->data;
 		if (size)
 			*size = file->size;
 		break;
diff --git a/libgphoto2/gphoto2-filesys.c b/libgphoto2/gphoto2-filesys.c
index 22a3d61e3..e746c1e90 100644
--- a/libgphoto2/gphoto2-filesys.c
+++ b/libgphoto2/gphoto2-filesys.c
@@ -113,12 +113,12 @@ get_time_from_exif_tag(ExifEntry *e) {
 	struct tm ts;
 
         e->data[4] = e->data[ 7] = e->data[10] = e->data[13] = e->data[16] = 0;
-        ts.tm_year = atoi (e->data) - 1900;
-        ts.tm_mon  = atoi (e->data + 5) - 1;
-        ts.tm_mday = atoi (e->data + 8);
-        ts.tm_hour = atoi (e->data + 11);
-        ts.tm_min  = atoi (e->data + 14);
-        ts.tm_sec  = atoi (e->data + 17);
+        ts.tm_year = atoi ((char*)e->data) - 1900;
+        ts.tm_mon  = atoi ((char*)(e->data + 5)) - 1;
+        ts.tm_mday = atoi ((char*)(e->data + 8));
+        ts.tm_hour = atoi ((char*)(e->data + 11));
+        ts.tm_min  = atoi ((char*)(e->data + 14));
+        ts.tm_sec  = atoi ((char*)(e->data + 17));
 
         return mktime (&ts);
 }