…r,Nilstrieb

target: default to the medium code model on LoongArch targets

The Rust LoongArch targets have been using the default LLVM code model so far, which is "small" in LLVM-speak and "normal" in LoongArch-speak. As [described][1] in the "Code Model" section of LoongArch ELF psABI spec v20231219, one can only make function calls as far as ±128MiB with the "normal" code model; this is insufficient for very large software containing Rust components that needs to be linked into the big text section, such as Chromium.

Because:

* we do not want to ask users to recompile std if they are to build such software,
* objects compiled with larger code models can be linked with those with smaller code models without problems, and
* the "medium" code model is comparable to the "small"/"normal" one performance-wise (same data access pattern; each function call becomes 2-insn long and indirect, but this may be relaxed back into the direct 1-insn form in a future LLVM version), but is able to perform function calls within ±128GiB,

it is better to just switch the targets to the "medium" code model, which is also "medium" in LLVM-speak.

[1]: https://github.com/loongson/la-abi-specs/blob/v2.30/laelf.adoc#code-models

…iaskrgr

Rollup of 9 pull requests

Successful merges:

 - rust-lang#113833 (`std::error::Error` -> Trait Implementations: lifetimes consistency improvement)
 - rust-lang#115386 (PartialEq, PartialOrd: update and synchronize handling of transitive chains)
 - rust-lang#116284 (make matching on NaN a hard error, and remove the rest of illegal_floating_point_literal_pattern)
 - rust-lang#118960 (Add LocalWaker and ContextBuilder types to core, and LocalWake trait to alloc.)
 - rust-lang#120384 (Use `<T, U>` for array/slice equality `impl`s)
 - rust-lang#120518 (riscv only supports split_debuginfo=off for now)
 - rust-lang#120619 (Assert that params with the same *index* have the same *name*)
 - rust-lang#120657 (Remove unused struct)
 - rust-lang#120661 (target: default to the medium code model on LoongArch targets)

r? `@ghost`
`@rustbot` modify labels: rollup

…iaskrgr

Rollup of 8 pull requests

Successful merges:

 - rust-lang#113833 (`std::error::Error` -> Trait Implementations: lifetimes consistency improvement)
 - rust-lang#115386 (PartialEq, PartialOrd: update and synchronize handling of transitive chains)
 - rust-lang#116284 (make matching on NaN a hard error, and remove the rest of illegal_floating_point_literal_pattern)
 - rust-lang#118960 (Add LocalWaker and ContextBuilder types to core, and LocalWake trait to alloc.)
 - rust-lang#120384 (Use `<T, U>` for array/slice equality `impl`s)
 - rust-lang#120518 (riscv only supports split_debuginfo=off for now)
 - rust-lang#120657 (Remove unused struct)
 - rust-lang#120661 (target: default to the medium code model on LoongArch targets)

r? `@ghost`
`@rustbot` modify labels: rollup

Rollup merge of rust-lang#120661 - xen0n:loong-medium-cmodel, r=heiher,Nilstrieb

target: default to the medium code model on LoongArch targets

The Rust LoongArch targets have been using the default LLVM code model so far, which is "small" in LLVM-speak and "normal" in LoongArch-speak. As [described][1] in the "Code Model" section of LoongArch ELF psABI spec v20231219, one can only make function calls as far as ±128MiB with the "normal" code model; this is insufficient for very large software containing Rust components that needs to be linked into the big text section, such as Chromium.

Because:

* we do not want to ask users to recompile std if they are to build such software,
* objects compiled with larger code models can be linked with those with smaller code models without problems, and
* the "medium" code model is comparable to the "small"/"normal" one performance-wise (same data access pattern; each function call becomes 2-insn long and indirect, but this may be relaxed back into the direct 1-insn form in a future LLVM version), but is able to perform function calls within ±128GiB,

it is better to just switch the targets to the "medium" code model, which is also "medium" in LLVM-speak.

[1]: https://github.com/loongson/la-abi-specs/blob/v2.30/laelf.adoc#code-models

…iler-errors

target: default to the medium code model on LoongArch targets

The Rust LoongArch targets have been using the default LLVM code model so far, which is "small" in LLVM-speak and "normal" in LoongArch-speak. As described in the "Code Model" section of LoongArch ELF psABI spec v20231219 [1], one can only make function calls as far as ±128MiB with the "normal" code model; this is insufficient for very large software containing Rust components that needs to be linked into the big text section, such as Chromium.

Because:

* we do not want to ask users to recompile std if they are to build such software,
* objects compiled with larger code models can be linked with those with smaller code models without problems, and
* the "medium" code model is comparable to the "small"/"normal" one performance-wise (same data access pattern; each function call becomes 2-insn long and indirect, but this may be relaxed back into the direct 1-insn form in a future LLVM version), but is able to perform function calls within ±128GiB,

it is better to just switch the targets to the "medium" code model, which is also "medium" in LLVM-speak.

Relands [2]:  rust-lang#120661

[1]: https://github.com/loongson/la-abi-specs/blob/v2.30/laelf.adoc#code-models
[2]: rust-lang#121289 (comment)

Rollup merge of rust-lang#130266 - heiher:loong-medium-cmodel, r=compiler-errors

target: default to the medium code model on LoongArch targets

The Rust LoongArch targets have been using the default LLVM code model so far, which is "small" in LLVM-speak and "normal" in LoongArch-speak. As described in the "Code Model" section of LoongArch ELF psABI spec v20231219 [1], one can only make function calls as far as ±128MiB with the "normal" code model; this is insufficient for very large software containing Rust components that needs to be linked into the big text section, such as Chromium.

Because:

* we do not want to ask users to recompile std if they are to build such software,
* objects compiled with larger code models can be linked with those with smaller code models without problems, and
* the "medium" code model is comparable to the "small"/"normal" one performance-wise (same data access pattern; each function call becomes 2-insn long and indirect, but this may be relaxed back into the direct 1-insn form in a future LLVM version), but is able to perform function calls within ±128GiB,

it is better to just switch the targets to the "medium" code model, which is also "medium" in LLVM-speak.

Relands [2]:  rust-lang#120661

[1]: https://github.com/loongson/la-abi-specs/blob/v2.30/laelf.adoc#code-models
[2]: rust-lang#121289 (comment)