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Let CStrings be either 1 or 2 byte aligned. #139785
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Let CStrings be either 1 or 2 byte aligned. #139785
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Some architectures (like s390x) require strings to be 2 byte aligned. Therefor the section name will be marked with a .2 postfix on this architectures. Allowing a section name with a .1 or .2 postfix will make the test pass on either platform.
rustbot has assigned @Mark-Simulacrum. Use |
Can you say more about this? Is this just in static strings embedded in the binary? In general we don't/can't guarantee that an arbitrary str is 2-byte aligned... |
I am not entirely sure but here are my insights: The s390x minimal alignment is set to 2 bytes here If this is not enough i'll ask @uweigand to elaborate further. |
hmm so i guess i need to rephrase: s390x requires global strings to be 2 byte aligned. |
Basically, the s390x ABI requires that every global symbol is at least 2 byte aligned. The reason is that our "load address (PC-relative)" instruction requires a minimum 2 byte alignment of its target address. |
@bors r+ |
…ignment, r=Mark-Simulacrum Let CStrings be either 1 or 2 byte aligned. We see a regression on the `tests/assembly/cstring-merging.rs` test on s390x. Some architectures (like s390x) require strings to be 2 byte aligned. Therefor the section name will be marked with a .2 postfix on this architectures. Allowing a section name with a .1 or .2 postfix will make the test pass on either platform.
Rollup of 11 pull requests Successful merges: - rust-lang#139669 (Overhaul `AssocItem`) - rust-lang#139671 (Proc macro span API redesign: Replace proc_macro::SourceFile by Span::{file, local_file}) - rust-lang#139750 (std/thread: Use default stack size from menuconfig for NuttX) - rust-lang#139785 (Let CStrings be either 1 or 2 byte aligned.) - rust-lang#139797 (Allow (but don't require) `#[unsafe(naked)]` so that `compiler-builtins` can upgrade to it) - rust-lang#139798 (normalize: prefer `ParamEnv` over `AliasBound` candidates) - rust-lang#139799 (Specify `--print info=file` syntax in `--help`) - rust-lang#139811 (Use `newtype_index!`-generated types more idiomatically) - rust-lang#139813 (Miri subtree update) - rust-lang#139822 (Fix: Map EOPNOTSUPP to ErrorKind::Unsupported on Unix) - rust-lang#139836 (Basic tests of MPMC receiver cloning) r? `@ghost` `@rustbot` modify labels: rollup
Rollup of 17 pull requests Successful merges: - rust-lang#138374 (Enable contracts for const functions) - rust-lang#138380 (ci: add runners for vanilla LLVM 20) - rust-lang#138393 (Allow const patterns of matches to contain pattern types) - rust-lang#139517 (std: sys: process: uefi: Use NULL stdin by default) - rust-lang#139554 (std: add Output::exit_ok) - rust-lang#139660 (compiletest: Add an experimental new executor to replace libtest) - rust-lang#139669 (Overhaul `AssocItem`) - rust-lang#139671 (Proc macro span API redesign: Replace proc_macro::SourceFile by Span::{file, local_file}) - rust-lang#139750 (std/thread: Use default stack size from menuconfig for NuttX) - rust-lang#139772 (Remove `hir::Map`) - rust-lang#139785 (Let CStrings be either 1 or 2 byte aligned.) - rust-lang#139789 (do not unnecessarily leak auto traits in item bounds) - rust-lang#139791 (drop global where-bounds before merging candidates) - rust-lang#139798 (normalize: prefer `ParamEnv` over `AliasBound` candidates) - rust-lang#139822 (Fix: Map EOPNOTSUPP to ErrorKind::Unsupported on Unix) - rust-lang#139833 (Fix some HIR pretty-printing problems) - rust-lang#139836 (Basic tests of MPMC receiver cloning) r? `@ghost` `@rustbot` modify labels: rollup
Rollup merge of rust-lang#139785 - fneddy:fix_test_cstring_merging_alignment, r=Mark-Simulacrum Let CStrings be either 1 or 2 byte aligned. We see a regression on the `tests/assembly/cstring-merging.rs` test on s390x. Some architectures (like s390x) require strings to be 2 byte aligned. Therefor the section name will be marked with a .2 postfix on this architectures. Allowing a section name with a .1 or .2 postfix will make the test pass on either platform.
Rollup of 17 pull requests Successful merges: - rust-lang#138374 (Enable contracts for const functions) - rust-lang#138380 (ci: add runners for vanilla LLVM 20) - rust-lang#138393 (Allow const patterns of matches to contain pattern types) - rust-lang#139517 (std: sys: process: uefi: Use NULL stdin by default) - rust-lang#139554 (std: add Output::exit_ok) - rust-lang#139660 (compiletest: Add an experimental new executor to replace libtest) - rust-lang#139669 (Overhaul `AssocItem`) - rust-lang#139671 (Proc macro span API redesign: Replace proc_macro::SourceFile by Span::{file, local_file}) - rust-lang#139750 (std/thread: Use default stack size from menuconfig for NuttX) - rust-lang#139772 (Remove `hir::Map`) - rust-lang#139785 (Let CStrings be either 1 or 2 byte aligned.) - rust-lang#139789 (do not unnecessarily leak auto traits in item bounds) - rust-lang#139791 (drop global where-bounds before merging candidates) - rust-lang#139798 (normalize: prefer `ParamEnv` over `AliasBound` candidates) - rust-lang#139822 (Fix: Map EOPNOTSUPP to ErrorKind::Unsupported on Unix) - rust-lang#139833 (Fix some HIR pretty-printing problems) - rust-lang#139836 (Basic tests of MPMC receiver cloning) r? `@ghost` `@rustbot` modify labels: rollup
We see a regression on the
tests/assembly/cstring-merging.rs
test on s390x.Some architectures (like s390x) require strings to be 2 byte aligned. Therefor the section name will be marked with a .2 postfix on this architectures.
Allowing a section name with a .1 or .2 postfix will make the test pass on either platform.