1 files changed, 12 insertions, 0 deletions
diff --git a/defines.h b/defines.h
index ef80989925..ae1277a6bf 100644
--- a/defines.h
+++ b/defines.h
@@ -254,6 +254,18 @@ __attribute__ ((noinline))
 #define ENV_IGNORECASE
 #endif
 
+#ifndef CASEFOLD_FILESYSTEM
+# if defined DOSISH || defined __VMS
+#   define CASEFOLD_FILESYSTEM 1
+# else
+#   define CASEFOLD_FILESYSTEM 0
+# endif
+#endif
+
+#ifndef DLEXT_MAXLEN
+#define DLEXT_MAXLEN 4
+#endif
+
 #ifndef RUBY_PLATFORM
 #define RUBY_PLATFORM "unknown-unknown"
 #endif