diff --git a/src/libstd/str.rs b/src/libstd/str.rs
index fafd2ecf7a5..1026b454c07 100644
--- a/src/libstd/str.rs
+++ b/src/libstd/str.rs
@@ -726,7 +726,7 @@ pub fn count_bytes<'b>(s: &'b str, start: uint, n: uint) -> uint {
 }
 
 // https://tools.ietf.org/html/rfc3629
-static UTF8_CHAR_WIDTH: [u8, ..256] = [
+priv static UTF8_CHAR_WIDTH: [u8, ..256] = [
 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // 0x1F
 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
@@ -757,15 +757,15 @@ pub struct CharRange {
 }
 
 // UTF-8 tags and ranges
-static TAG_CONT_U8: u8 = 128u8;
-static TAG_CONT: uint = 128u;
-static MAX_ONE_B: uint = 128u;
-static TAG_TWO_B: uint = 192u;
-static MAX_TWO_B: uint = 2048u;
-static TAG_THREE_B: uint = 224u;
-static MAX_THREE_B: uint = 65536u;
-static TAG_FOUR_B: uint = 240u;
-static MAX_UNICODE: uint = 1114112u;
+priv static TAG_CONT_U8: u8 = 128u8;
+priv static TAG_CONT: uint = 128u;
+priv static MAX_ONE_B: uint = 128u;
+priv static TAG_TWO_B: uint = 192u;
+priv static MAX_TWO_B: uint = 2048u;
+priv static TAG_THREE_B: uint = 224u;
+priv static MAX_THREE_B: uint = 65536u;
+priv static TAG_FOUR_B: uint = 240u;
+priv static MAX_UNICODE: uint = 1114112u;
 
 /// Unsafe operations
 pub mod raw {