diff --git a/src/librustc/session/mod.rs b/src/librustc/session/mod.rs
index fa9bc7c8368..5901c42b525 100644
--- a/src/librustc/session/mod.rs
+++ b/src/librustc/session/mod.rs
@@ -126,20 +126,14 @@ impl Session {
                                                    sp: S,
                                                    msg: &str)
                                                    -> DiagnosticBuilder<'a>  {
-        match split_msg_into_multilines(msg) {
-            Some(ref msg) => self.diagnostic().struct_span_err(sp, msg),
-            None => self.diagnostic().struct_span_err(sp, msg),
-        }
+        self.diagnostic().struct_span_err(sp, msg)
     }
     pub fn struct_span_err_with_code<'a, S: Into<MultiSpan>>(&'a self,
                                                              sp: S,
                                                              msg: &str,
                                                              code: &str)
                                                              -> DiagnosticBuilder<'a>  {
-        match split_msg_into_multilines(msg) {
-            Some(ref msg) => self.diagnostic().struct_span_err_with_code(sp, msg, code),
-            None => self.diagnostic().struct_span_err_with_code(sp, msg, code),
-        }
+        self.diagnostic().struct_span_err_with_code(sp, msg, code)
     }
     pub fn struct_err<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a>  {
         self.diagnostic().struct_err(msg)
@@ -178,16 +172,10 @@ impl Session {
         }
     }
     pub fn span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
-        match split_msg_into_multilines(msg) {
-            Some(msg) => self.diagnostic().span_err(sp, &msg),
-            None => self.diagnostic().span_err(sp, msg)
-        }
+        self.diagnostic().span_err(sp, msg)
     }
     pub fn span_err_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: &str) {
-        match split_msg_into_multilines(msg) {
-            Some(msg) => self.diagnostic().span_err_with_code(sp, &msg, code),
-            None => self.diagnostic().span_err_with_code(sp, msg, code)
-        }
+        self.diagnostic().span_err_with_code(sp, &msg, code)
     }
     pub fn err(&self, msg: &str) {
         self.diagnostic().err(msg)
@@ -343,67 +331,6 @@ impl Session {
     }
 }
 
-fn split_msg_into_multilines(msg: &str) -> Option<String> {
-    // Conditions for enabling multi-line errors:
-    if !msg.contains("mismatched types") &&
-        !msg.contains("type mismatch resolving") &&
-        !msg.contains("if and else have incompatible types") &&
-        !msg.contains("if may be missing an else clause") &&
-        !msg.contains("match arms have incompatible types") &&
-        !msg.contains("structure constructor specifies a structure of type") &&
-        !msg.contains("has an incompatible type for trait") {
-            return None
-    }
-    let first = msg.match_indices("expected").filter(|s| {
-        let last = msg[..s.0].chars().rev().next();
-        last == Some(' ') || last == Some('(')
-    }).map(|(a, b)| (a - 1, a + b.len()));
-    let second = msg.match_indices("found").filter(|s| {
-        msg[..s.0].chars().rev().next() == Some(' ')
-    }).map(|(a, b)| (a - 1, a + b.len()));
-
-    let mut new_msg = String::new();
-    let mut head = 0;
-
-    // Insert `\n` before expected and found.
-    for (pos1, pos2) in first.zip(second) {
-        new_msg = new_msg +
-        // A `(` may be preceded by a space and it should be trimmed
-                  msg[head..pos1.0].trim_right() + // prefix
-                  "\n" +                           // insert before first
-                  &msg[pos1.0..pos1.1] +           // insert what first matched
-                  &msg[pos1.1..pos2.0] +           // between matches
-                  "\n   " +                        // insert before second
-        //           123
-        // `expected` is 3 char longer than `found`. To align the types,
-        // `found` gets 3 spaces prepended.
-                  &msg[pos2.0..pos2.1];            // insert what second matched
-
-        head = pos2.1;
-    }
-
-    let mut tail = &msg[head..];
-    let third = tail.find("(values differ")
-                   .or(tail.find("(lifetime"))
-                   .or(tail.find("(cyclic type of infinite size"));
-    // Insert `\n` before any remaining messages which match.
-    if let Some(pos) = third {
-        // The end of the message may just be wrapped in `()` without
-        // `expected`/`found`.  Push this also to a new line and add the
-        // final tail after.
-        new_msg = new_msg +
-        // `(` is usually preceded by a space and should be trimmed.
-                  tail[..pos].trim_right() + // prefix
-                  "\n" +                     // insert before paren
-                  &tail[pos..];              // append the tail
-
-        tail = "";
-    }
-
-    new_msg.push_str(tail);
-    return Some(new_msg);
-}
-
 pub fn build_session(sopts: config::Options,
                      dep_graph: &DepGraph,
                      local_crate_source_file: Option<PathBuf>,