Don't print the macro definition site in backtraces

This halves the backtrace length. The definition site wasn't very useful
anyways, since it may be invalid (for compiler expansions) or located in
another crate. Since the macro name is still printed, grepping for it is
still an easy way of finding the definition.

1 files changed, 2 insertions, 6 deletions

diff --git a/src/libsyntax/diagnostic.rs b/src/libsyntax/diagnostic.rs
index 1924368a7f5..c383f26b4e3 100644
--- a/src/libsyntax/diagnostic.rs
+++ b/src/libsyntax/diagnostic.rs
@@ -732,21 +732,17 @@ impl EmitterWriter {
             sp_opt = try!(cm.with_expn_info(sp.expn_id, |expn_info| -> io::Result<_> {
                 match expn_info {
                     Some(ei) => {
-                        let ss = ei.callee.span.map_or(String::new(),
-                                                       |span| cm.span_to_string(span));
                         let (pre, post) = match ei.callee.format {
                             codemap::MacroAttribute(..) => ("#[", "]"),
                             codemap::MacroBang(..) => ("", "!"),
                             codemap::CompilerExpansion(..) => ("", ""),
                         };
-                        try!(self.print_diagnostic(&ss, Note,
-                                                   &format!("in expansion of {}{}{}",
+                        try!(self.print_diagnostic(&cm.span_to_string(ei.call_site), Note,
+                                                   &format!("in this expansion of {}{}{}",
                                                             pre,
                                                             ei.callee.name(),
                                                             post),
                                                    None));
-                        let ss = cm.span_to_string(ei.call_site);
-                        try!(self.print_diagnostic(&ss, Note, "expansion site", None));
                         Ok(Some(ei.call_site))
                     }
                     None => Ok(None)