Currently they have the largest items at the end. I believe the
rationale is that it saves you scrolling up through terminal output
because the important stuff is at the bottom. But it's also surprising
and a bit confusing, and I think the obvious order (big things at the
top) is better.
Taking inspiration from `-Zmacro-stats`:
- Use "{prefix}" consistently.
- Use names for column widths.
- Write output in a single `eprint!` call, in an attempt to minimize
interleaving of output from different rustc processes.
- Use `repeat` for the long `---` banners.
It currently reports net size, i.e. size(output) - size(input). After
some use I think this is sub-optimal, and it's better to just report
size(output). Because for derive macros the input size is always 1, and
for attribute macros it's almost always 1.
fix `-Zmin-function-alignment` on functions without attributes
tracking issue: https://github.com/rust-lang/rust/issues/82232
related: https://github.com/rust-lang/rust/pull/142854
The minimum function alignment was skipped on functions without attributes (because the logic was in a loop that only runs if there is at least one attribute). The underlying reason we didn't catch this before is that in our testing we generally apply `#[no_mangle]` to functions that are tested. I've added a test now that deliberately has no attributes.
r? `@workingjubilee`
Add codegen timing section
And since we now start and end the sections also using separate functions, also add some light checking if we're generating the sections correctly.
I'm integrating `--timings` into Cargo, and I realized that the codegen timings would be quite useful for that. Frontend can be computed simply as `[start of compilation, start of codegen]` for now.
r? `@nnethercote`
the minimum function alignment was skipped on functions without attributes. That is because in our testing we generally apply `#[no_mangle]` to functions that are tested. I've added a test now that deliberately has no attributes
We modify rustc_ast_lowering to prevent all unsupported ABIs
from leaking through the HIR without being checked for target support.
Previously ad-hoc checking on various HIR items required making sure
we check every HIR item which could contain an `extern "{abi}"` string.
This is a losing proposition compared to gating the lowering itself.
As a consequence, unsupported ABI strings will now hard-error instead of
triggering the FCW `unsupported_fn_ptr_calling_conventions`.
This FCW was upgraded to warn in dependencies in Rust 1.87 which was
released on 2025 May 17, and it is now 2025 June, so it has become
active within a stable Rust version.
As we already had errored on these ABIs in most other positions, and
have warned for fn ptrs, this breakage has had reasonable foreshadowing.
However, this does cause errors for usages of `extern "{abi}"` that were
theoretically writeable within source but could not actually be applied
in any useful way by Rust programmers without either warning or error.
For instance, trait declarations without impls were never checked.
These are the exact kinds of leakages that this new approach prevents.
A deprecation cycle is not useful for these marginal cases as upon impl,
even default impls within traits, different HIR objects would be used.
Details of our HIR analysis meant that those objects did get checked.
We choose to error twice if an ABI is also barred by a feature gate
on the presumption that usage of a target-incorrect ABI is intentional.
Co-authored-by: Ralf Jung <post@ralfj.de>
Fix ICE on debug builds where lints are delayed on the crate root
r? ``@oli-obk``
Closesrust-lang/rust#142891
thanks to ``@JonathanBrouwer`` for finding it!
centralize `-Zmin-function-alignment` logic
tracking issue: https://github.com/rust-lang/rust/issues/82232
discussed in: https://github.com/rust-lang/rust/pull/142824#discussion_r2160056244
Apply the `-Zmin-function-alignment` value to the alignment field of the function attributes when those are created, so that individual backends don't need to consider it.
The one exception right now is cranelift, because it can't yet set the alignment for individual functions, but it can (and does) set the global minimum function alignment.
cc ``@RalfJung`` I think this is an improvement regardless, is there anything else that should be done for miri?
Skip no-op drop glue
Since rust-lang/rust#122662 this no longer gets used in vtables, so we're safe to fully
drop generating functions from vtables. Those are eventually cleaned up
by LLVM, but it's wasteful to produce them in the first place.
This doesn't appear to be a significant win (and shows some slight regressions) but
seems like the right thing to do. At minimum it reduces noise in the LLVM IR we generate,
which seems like a good thing.
Rollup of 10 pull requests
Successful merges:
- rust-lang/rust#142458 (Merge unboxed trait object error suggestion into regular dyn incompat error)
- rust-lang/rust#142593 (Add a warning to LateContext::get_def_path)
- rust-lang/rust#142594 (Add DesugaringKind::FormatLiteral)
- rust-lang/rust#142740 (Clean-up `FnCtxt::is_destruct_assignment_desugaring`)
- rust-lang/rust#142780 (Port `#[must_use]` to new attribute parsing infrastructure)
- rust-lang/rust#142798 (Don't fail to parse a struct if a semicolon is used to separate fields)
- rust-lang/rust#142856 (Add a few inline directives in rustc_serialize.)
- rust-lang/rust#142868 (remove few allow(dead_code))
- rust-lang/rust#142874 (cranelift: fix target feature name typo: "fxsr")
- rust-lang/rust#142877 (Document why tidy checks if `eslint` is installed via `npm`)
r? `@ghost`
`@rustbot` modify labels: rollup
Add a few inline directives in rustc_serialize.
I see `debug_strict_add` and `debug_strict_sub` appearing in callgrind output. This bothers me. This PR should make them disappear.
