span_to_snippet is broken

[emberian]

Passing it a span that I get from rustc fails with:

rust: task failed at 'assertion failed: (left == right) && (right == left) (left: {__field__: 9860}, right: {__field__: 57921})', /home/cmr/hacking/rust-benching/src/libsyntax/codemap.rs:376

To reproduce: build dd598e1 from cmr/rustdoc_ng, run it on libstd.

@jbclements maybe?

[catamorphism]

@cmr I can't compile that revision of rustdoc_ng with rust HEAD anymore. If you get a chance, can you try to reproduce it? (Don't worry about this too much; it's not high priority anyway.)

[emberian]

@catamorphism sure, I'll try and get to this tomorrow.

[emberian]

(The tomorrow that never came)