Merge branch 'master' into issue-30961

2 files changed, 6 insertions, 4 deletions

diff --git a/src/libstd/sys/common/mod.rs b/src/libstd/sys/common/mod.rs
index c9279883ae5..a1f3f477b3a 100644
--- a/src/libstd/sys/common/mod.rs
+++ b/src/libstd/sys/common/mod.rs
@@ -28,6 +28,7 @@ macro_rules! rtassert {
 
 pub mod args;
 pub mod at_exit_imp;
+#[cfg(any(not(cargobuild), feature = "backtrace"))]
 pub mod backtrace;
 pub mod condvar;
 pub mod io;
@@ -42,6 +43,7 @@ pub mod thread_local;
 pub mod util;
 pub mod wtf8;
 
+#[cfg(any(not(cargobuild), feature = "backtrace"))]
 #[cfg(any(all(unix, not(any(target_os = "macos", target_os = "ios", target_os = "emscripten"))),
           all(windows, target_env = "gnu")))]
 pub mod gnu;
diff --git a/src/libstd/sys/common/wtf8.rs b/src/libstd/sys/common/wtf8.rs
index 2c1a656290f..c1b4f8a8c88 100644
--- a/src/libstd/sys/common/wtf8.rs
+++ b/src/libstd/sys/common/wtf8.rs
@@ -390,7 +390,7 @@ impl fmt::Debug for Wtf8 {
     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
         fn write_str_escaped(f: &mut fmt::Formatter, s: &str) -> fmt::Result {
             use fmt::Write;
-            for c in s.chars().flat_map(|c| c.escape_default()) {
+            for c in s.chars().flat_map(|c| c.escape_debug()) {
                 f.write_char(c)?
             }
             Ok(())
@@ -408,7 +408,7 @@ impl fmt::Debug for Wtf8 {
                             &self.bytes[pos .. surrogate_pos]
                         )},
                     )?;
-                    write!(formatter, "\\u{{{:X}}}", surrogate)?;
+                    write!(formatter, "\\u{{{:x}}}", surrogate)?;
                     pos = surrogate_pos + 3;
                 }
             }
@@ -1064,9 +1064,9 @@ mod tests {
 
     #[test]
     fn wtf8buf_show() {
-        let mut string = Wtf8Buf::from_str("a\té 💩\r");
+        let mut string = Wtf8Buf::from_str("a\té \u{7f}💩\r");
         string.push(CodePoint::from_u32(0xD800).unwrap());
-        assert_eq!(format!("{:?}", string), r#""a\t\u{e9} \u{1f4a9}\r\u{D800}""#);
+        assert_eq!(format!("{:?}", string), "\"a\\té \\u{7f}\u{1f4a9}\\r\\u{d800}\"");
     }
 
     #[test]