Re-enable corrected error line printing and highlighting

[jdm]

make fast-check now works correctly, as does regular check.

[brson]

I saw you mention this on IRC, but if I put a syntax error in, e.g. lib/str.rs, by writting "bogus" on line 1, the compiler errors with

../src/lib/str.rs:1:23942:1:23942: error: expected item but found bogus
../src/lib/str.rs:1 rt: ---
rt: d76f:main:main:                   upcall fail 'Assertion begin <= end failed', /media/src/rust-tinderbox/srcdir-snap-stage3-x86_64-unknown-linux-gnu/src/lib/str.rs:392
rt: d76f:main:                        domain main @0x9269db8 root task failed

which is wrong

[brson]

Oh, I see that existed before this patch

[jdm]

I'm closing this for now until I work out the kinks, such as having errors on the first line. I'm not entirely sure what's up.

[brson]

This is looking good, but I see one more related problem it would be nice to fix before reenabling this. If i modify lib/str.rs to write "bogus" on line 53, like:

export unsafe_from_bytes_ivec;
bogus
native "rust" mod rustrt {

then run make stage1/lib/libstd.so, the error printed ends up dumping out the entirety of str.rs from 'bogus' on (it's hitting the 'if ((line as uint) + 1u >= vec::len(fm.lines))' case in get_line.

This behavior is kind of unfriendly, can we make this case, instead of printing the rest of the file, just print up to the next newline?