Don't expose redundant information in rustc_public's LayoutShape
#151040
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Enum variant layouts don't need to store a full `LayoutShape`; just storing
the fields offsets is enough and all other information can be inferred from
the parent layout:
- size, align and ABI don't make much sense for individual variants and
should generally be taken from the parent layout instead;
- variants always have `fields: FieldsShape::Arbitrary { .. }` and
`variant: VariantShape::Single { .. }`.
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⌛ Testing commit 3777ebc with merge 7cfb9e0... Workflow: https://github.com/rust-lang/rust/actions/runs/21367599744 |
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Don't expose redundant information in `rustc_public`'s `LayoutShape`
Enum variant layouts don't need to store a full `LayoutShape`; just storing the fields offsets is enough and all other information can be inferred from the parent layout:
- size, align and ABI don't make much sense for individual variants and should generally be taken from the parent layout instead;
- variants always have `fields: FieldsShape::Arbitrary { .. }` and `variant: VariantShape::Single { .. }`.
In principle, the same refactor could be done on `rustc_abi::Layout` (see [this comment](#113988 (comment))) but I prefer starting with this smaller change first.
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Auto build cancelled. Cancelled workflows: The next pull request likely to be tested is #151040. |
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…akai410
Don't expose redundant information in `rustc_public`'s `LayoutShape`
Enum variant layouts don't need to store a full `LayoutShape`; just storing the fields offsets is enough and all other information can be inferred from the parent layout:
- size, align and ABI don't make much sense for individual variants and should generally be taken from the parent layout instead;
- variants always have `fields: FieldsShape::Arbitrary { .. }` and `variant: VariantShape::Single { .. }`.
In principle, the same refactor could be done on `rustc_abi::Layout` (see [this comment](rust-lang#113988 (comment))) but I prefer starting with this smaller change first.
matthiaskrgr
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…akai410
Don't expose redundant information in `rustc_public`'s `LayoutShape`
Enum variant layouts don't need to store a full `LayoutShape`; just storing the fields offsets is enough and all other information can be inferred from the parent layout:
- size, align and ABI don't make much sense for individual variants and should generally be taken from the parent layout instead;
- variants always have `fields: FieldsShape::Arbitrary { .. }` and `variant: VariantShape::Single { .. }`.
In principle, the same refactor could be done on `rustc_abi::Layout` (see [this comment](rust-lang#113988 (comment))) but I prefer starting with this smaller change first.
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…akai410
Don't expose redundant information in `rustc_public`'s `LayoutShape`
Enum variant layouts don't need to store a full `LayoutShape`; just storing the fields offsets is enough and all other information can be inferred from the parent layout:
- size, align and ABI don't make much sense for individual variants and should generally be taken from the parent layout instead;
- variants always have `fields: FieldsShape::Arbitrary { .. }` and `variant: VariantShape::Single { .. }`.
In principle, the same refactor could be done on `rustc_abi::Layout` (see [this comment](rust-lang#113988 (comment))) but I prefer starting with this smaller change first.
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Rollup of 6 pull requests Successful merges: - #148718 (Do not mention `-Zmacro-backtrace` for std macros that are a wrapper around a compiler intrinsic) - #151137 (checksum-freshness: Fix invalid checksum calculation for binary files) - #150863 (Adds two new Tier 3 targets - `aarch64v8r-unknown-none{,-softfloat}`) - #151040 (Don't expose redundant information in `rustc_public`'s `LayoutShape`) - #151699 (Update books) - #151700 (os allow missing_docs)
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Rollup of 12 pull requests Successful merges: - #147996 (Stabilize ppc inline assembly) - #148718 (Do not mention `-Zmacro-backtrace` for std macros that are a wrapper around a compiler intrinsic) - #151137 (checksum-freshness: Fix invalid checksum calculation for binary files) - #151680 (Update backtrace and windows-bindgen) - #150863 (Adds two new Tier 3 targets - `aarch64v8r-unknown-none{,-softfloat}`) - #151040 (Don't expose redundant information in `rustc_public`'s `LayoutShape`) - #151383 (remove `#[deprecated]` from unstable & internal `SipHasher13` and `24` types) - #151529 (lint: Use rustc_apfloat for `overflowing_literals`, add f16 and f128) - #151669 (rename uN::{gather,scatter}_bits to uN::{extract,deposit}_bits) - #151689 (Fix broken Xtensa installation link) - #151699 (Update books) - #151700 (os allow missing_docs)
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Rollup merge of #151040 - moulins:public-variant-layout, r=makai410 Don't expose redundant information in `rustc_public`'s `LayoutShape` Enum variant layouts don't need to store a full `LayoutShape`; just storing the fields offsets is enough and all other information can be inferred from the parent layout: - size, align and ABI don't make much sense for individual variants and should generally be taken from the parent layout instead; - variants always have `fields: FieldsShape::Arbitrary { .. }` and `variant: VariantShape::Single { .. }`. In principle, the same refactor could be done on `rustc_abi::Layout` (see [this comment](#113988 (comment))) but I prefer starting with this smaller change first.
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Rollup of 12 pull requests Successful merges: - rust-lang/rust#147996 (Stabilize ppc inline assembly) - rust-lang/rust#148718 (Do not mention `-Zmacro-backtrace` for std macros that are a wrapper around a compiler intrinsic) - rust-lang/rust#151137 (checksum-freshness: Fix invalid checksum calculation for binary files) - rust-lang/rust#151680 (Update backtrace and windows-bindgen) - rust-lang/rust#150863 (Adds two new Tier 3 targets - `aarch64v8r-unknown-none{,-softfloat}`) - rust-lang/rust#151040 (Don't expose redundant information in `rustc_public`'s `LayoutShape`) - rust-lang/rust#151383 (remove `#[deprecated]` from unstable & internal `SipHasher13` and `24` types) - rust-lang/rust#151529 (lint: Use rustc_apfloat for `overflowing_literals`, add f16 and f128) - rust-lang/rust#151669 (rename uN::{gather,scatter}_bits to uN::{extract,deposit}_bits) - rust-lang/rust#151689 (Fix broken Xtensa installation link) - rust-lang/rust#151699 (Update books) - rust-lang/rust#151700 (os allow missing_docs)
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Enum variant layouts don't need to store a full
LayoutShape; just storing the fields offsets is enough and all other information can be inferred from the parent layout:fields: FieldsShape::Arbitrary { .. }andvariant: VariantShape::Single { .. }.In principle, the same refactor could be done on
rustc_abi::Layout(see this comment) but I prefer starting with this smaller change first.