diff --git a/lib/setup.h b/lib/setup.h
index 4268b9bf6a3288f7ca6a7a3528a512b263029a95..c1f7135e54438abea007b51c8d20c59c596f7ef9 100644
--- a/lib/setup.h
+++ b/lib/setup.h
@@ -323,7 +323,8 @@
 #    if defined(_LP64) || defined(_LARGE_FILES)
 #      define SIZEOF_OFF_T 8
 #    endif
-#  else
+#  endif
+#  ifndef SIZEOF_OFF_T
 #    define SIZEOF_OFF_T 4
 #  endif
 #endif
diff --git a/src/main.c b/src/main.c
index 62c34cbdfbab8d85ac419909d680b2ee744b0705..784d1750fd9a38c056ff290094b076c8d4592c9b 100644
--- a/src/main.c
+++ b/src/main.c
@@ -263,7 +263,8 @@ typedef enum {
 #    if defined(_LP64) || defined(_LARGE_FILES)
 #      define SIZEOF_OFF_T 8
 #    endif
-#  else
+#  endif
+#  ifndef SIZEOF_OFF_T
 #    define SIZEOF_OFF_T 4
 #  endif
 #endif