auto merge of #14517 : lucy/rust/issue-14499, r=alexcrichton

Fixes #8537
Fixes #14499 (duplicate of #8537)

Old:
```rust
test.rs:2 	pub extern "xxxxx" fn add(x: int, y: int) -> int {
          	                   ^~
```

New:
```rust
test.rs:2 	pub extern "xxxxx" fn add(x: int, y: int) -> int {
          	           ^~~~~~~
```

src/libsyntax/parse/parser.rs

@@ -4537,7 +4537,7 @@ impl<'a> Parser<'a> {
                     Some(abi) => Some(abi),
                     None => {
                         self.span_err(
-                            self.span,
+                            self.last_span,
                             format!("illegal ABI: expected one of [{}], \
                                      found `{}`",
                                     abi::all_names().connect(", "),