Merge pull request #4951 from Reckordp/master

Fix unfinished changes

mrbgems/mruby-io/src/file.c

@@ -283,9 +283,11 @@ static int
 mrb_file_is_absolute_path(const char *path)
 {
 #ifdef _WIN32
-#define IS_PATHSEP(x) (x == '/' || x == '\')
-  if (strlen(path) < 3) return 0;
-  return (isalpha(path[0]) && path[1] == ':' && IS_PATHSEP(path[2]));
+#define IS_PATHSEP(x) (x == '/' || x == '\\')
+  if (isalpha(path[0]))
+    return (strlen(path) > 2 && path[1] == ':' && IS_PATHSEP(path[2]));
+  else
+    return (IS_PATHSEP(path[0]) && IS_PATHSEP(path[1]));
 #undef IS_PATHSEP
 #else
   return (path[0] == '/');