The easter egg ICE on `break rust` is weird: it's the one ICE in the
entire compiler that doesn't immediately abort, which makes it
annoyingly inconsistent.
This commit changes it to abort. As part of this, the extra notes are
now appended onto the bug dignostic, rather than being printed as
individual note diagnostics, which changes the output format a bit.
These changes don't interferes with the joke, but they do help with my
ongoing cleanups to error handling.
Previously, we would normalize *all* of
- the absolute path to the repository checkout
- the /rustc/$sha for stage1 (if `remap-debuginfo` was enabled)
- the /rustc/$sha for download-rustc
- the sysroot for download-rustc
Now, we consistently only normalize /rustc/FAKE_PREFIX. Not only is this
much simpler, but it also avoids ongoing maintenance for download-rustc
and makes it much less likely that tests break by accident.
- Change `tests/ui/track-diagnostics/track6.rs` to use a relative path
instead of an absolute one. I am not actually sure why `track_caller`
works here, but it does seem to work 🤷
- Pass `-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX` to all
suites, not just UI. In particular, mir-opt tests emit /rustc/ paths
in their output.
This is really a mess. Here is the situation before this change:
- UI tests depend on not having `rust-src` available. In particular, <3f374128ee/tests/ui/tuple/wrong_argument_ice.stderr (L7-L8)> is depending on the `note` being a single line and not showing the source code.
- When `download-rustc` is disabled, we pass `-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX` `-Ztranslate-remapped-path-to-local-path=no`, which changes the diagnostic to something like ` --> /rustc/FAKE_PREFIX/library/alloc/src/collections/vec_deque/mod.rs:1657:12`
- When `download-rustc` is enabled, we still pass those flags, but they no longer have an effect. Instead rustc emits diagnostic paths like this: ` --> /rustc/39c6804b92aa202369e402525cee329556bc1db0/library/alloc/src/collections/vec_deque/mod.rs:1657:12`. Notice how there's a real commit and not `FAKE_PREFIX`. This happens because we set `CFG_VIRTUAL_RUST_SOURCE_BASE_DIR` during bootstrapping for CI artifacts, and rustc previously didn't allow for `simulate-remapped` to affect paths that had already been remapped.
- Pietro noticed this and decided the right thing was to normalize `/rustc/<commit>` to `$SRC_DIR` in compiletest: 470423c3d2
- After my change to `x test core`, which rebuilds stage 2 std from source so `build/stage2-std` and `build/stage2` use the same `.rlib` metadata, the compiler suddenly notices it has sources for `std` available and prints those in the diagnostic, causing the test to fail.
This changes `simulate-remapped-rust-src-base` to support remapping paths that have already been remapped, unblocking download-rustc.
Unfortunately, although this fixes the specific problem for
download-rustc, it doesn't seem to affect all the compiler's
diagnostics. In particular, various `mir-opt` tests are failing to
respect `simulate-remapped-path-prefix` (I looked into fixing this but
it seems non-trivial). As a result, we can't remove the normalization in
compiletest that maps `/rustc/<commit>` to `$SRC_DIR`, so this change is
currently untested anywhere except locally.
