impl ICE

[jesse99]

Added , ToStr to an impl and the compiler ICEd with

rust: task failed at 'multiple traits!!', /Users/jessejones/Source/Third_Party/rust/src/rustc/metadata/encoder.rs:716
error: internal compiler error: unexpected failure

Was not able to boil this down to a simple repro, but rrdf commit 8fe284d4d08677d00a3eefb5180549d43faeec98 fails with rust from master on Sep 1.

Was able to work around this by adding a dedicated ToStr impl.

[catamorphism]

I'll look.

[catamorphism]

@pcwalton says that multiple traits in an impl are not legal anymore. I'll make it so that you get a better error than an ICE.

[jesse99]

Perhaps the Sep 1 master was in some half-baked intermediate state but when I tried to produce a simple test case it compiled and ran.

[catamorphism]

Did your test case have the impl in the same crate with code that used the impl? That was working, I think, but using an impl with multiple traits cross-crate isn't.