test std more systematically

[RalfJung]

Now that rustc itself already runs std tests in CI, it wouldn't make sense to just do the exact same thing here. So let's see if we can test more.

[RalfJung]

  0.066767   error: multiple definitions of symbol `lgammaf_r`
  0.000046       --> /home/runner/work/miri-test-libstd/miri-test-libstd/rust-src-patched/library/std/src/f32.rs:1196:26
  0.000008        |
  0.000007   1196 |         let x = unsafe { cmath::lgammaf_r(self, &mut signgamp) };
  0.000005        |                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ multiple definitions of symbol `lgammaf_r`
  0.000006        |

So, blocked by rust-lang/compiler-builtins#586.

[RalfJung]

Now blocked on rust-lang/rust#123719 and rust-lang/rust#123891.

[RalfJung]

Now blocked on rust-lang/rust#123957 and rust-lang/rust#124007

[RalfJung]

Next blocker: rust-lang/miri#3499

[RalfJung]

I think that failure is an instance of rust-lang/rust#124409.

[RalfJung]

Next blocker: rust-lang/rust#124411

[RalfJung]

Yay, finally. :)