Closures cause ICE with -Z debug-info

[chris-morgan]

Yep, it seems that any use of closures (assuming they don't get optimised out of existence) is broken.

rust 0.8-pre (0efbb25 2013-08-13 23:59:18 -0700)
host: x86_64-unknown-linux-gnu

For example:

$ echo 'fn main() { let _a = ||(); }' | rustc - -Z debug-info
<anon>:1:23: 1:25 error: internal compiler error: debuginfo: FunctionDebugContext should be initialized but is not!
<anon>:1 fn main() { let _a = ||(); }
                                ^~

CC @michaelwoerister

[michaelwoerister]

I'll look into it. Quite a bit of closure code already works fine (e.g. https://github.com/mozilla/rust/blob/master/src/test/debug-info/lexical-scope-in-stack-closure.rs). This may also be caused by only compiling with -Z debug-info instead of -Z extra-debug-info.

In any case, I'll try to solve this asap :)

[michaelwoerister]

This will be fixed with my next PR. It's a corner case where no other code (like parameter description) initialized the FunctionDebugContext before its scope map was queried.