Regression report stable-2015-08-06 vs. nightly-2015-09-04

[brson]

Regression report stable-2015-08-06 vs. nightly-2015-09-04

• From: stable-2015-08-06
• To: nightly-2015-09-04

Coverage

• 2938 crates tested: 1594 working / 1125 broken / 22 regressed / 184 fixed / 13 unknown.

Regressions

• There are 12 root regressions
• There are 22 regressions

Root regressions, sorted by rank:

• nickel-0.6.0 (before) (after)
• piston-gfx_texture-0.3.0 (before) (after)
• pod-0.3.1 (before) (after)
• glium_text-0.5.1 (before) (after)
• immeta-0.1.0 (before) (after)
• influent-0.1.0 (before) (after)
• lux-0.0.2 (before) (after)
• cuckoofilter-0.2.0 (before) (after)
• rcon-0.0.3 (before) (after)
• rustache-0.0.1 (before) (after)
• elf-0.0.5 (before) (after)
• terminal_thrift-0.3.1 (before) (after)

Full report.

Analysis

This run is five days old, so some things may have changed. There’s quite a bit of breakage here, some the same as previously.

This stuff is going to hit beta next week.

• cannot infer lifetime - nickel
  • probably fallout from https://github.com/rust-lang/rfcs/blob/master/text/1214-projections-lifetimes-and-wf.md
• ICE - piston-gfx_texture, glium_text, lux
  • supposedly fixed on master. I’ll make another run now
• read_exact became unstable? - pod, immeta, rcon, byteorder, terminal_thrift
  • I don’t understand what’s going on here. Compiles on stable, but read_exact unstable on master.
• wrong number of lifetime parameters - influent
  • no idea
• unresolved std::hash import - cuckoofilter
  • fallout from a bug where import lists aren’t checked for stability.
• unused_mut lint - rustache
  • acceptable lint change

The read_exact thing is a mess. @bluss suggests it’s a conflict with custom implementations that already existed.

[jschievink]

This reproduces the influent regression:

trait Tr {}

struct S<'a>(&'a str);

fn f(a: S, b: Box<Tr>) -> S { a }

Works on stable, not on nightly. Using another S instead of the Box<Tr> always fails, as expected.

[eefriedman]

That testcase looks like https://github.com/rust-lang/rust/issues/27248 .

[brson]

Thanks for the tips @jschievink @eefriedman. I’ll investigate whether we can get that fixed.