Make #[used(linker)] the default on ELF too #140872
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#[used] currently is an alias for #[used(linker)] on all platforms except ELF based ones where it is an alias for #[used(compiler)]. The latter has surprising behavior and the LLVM LangRef explicitly states that it "should only be used in rare circumstances, and should not be exposed to source languages." The reason #[used] still was an alias to #[used(compiler)] on ELF is because the gold linker has issues with it. Luckily gold has been deprecated with GCC 15 and seems to be unable to bootstrap rustc anyway. As such we shouldn't really care about supporting gold.
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r? @nnethercote rustbot has assigned @nnethercote. Use |
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Some changes occurred in compiler/rustc_codegen_ssa Some changes occurred in compiler/rustc_codegen_ssa/src/codegen_attrs.rs |
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This was referenced May 9, 2025
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#[used]currently is an alias for#[used(linker)]on all platforms except ELF based ones where it is an alias for#[used(compiler)]. The latter has surprising behavior and the LLVM LangRef explicitly states that it "should only be used in rare circumstances, and should not be exposed to source languages."The reason
#[used]still was an alias to#[used(compiler)]on ELF is because the gold linker has issues with it. Luckily gold has been deprecated with GCC 15 and seems to be unable to bootstrap rustc anyway 1. As such we shouldn't really care about supporting gold.This would also allow re-enabling start-stop-gc with lld.
cc #93798
Likely fixes #85045
Likely fixes #99721
Footnotes
https://llvm.org/docs/LangRef.html#the-llvm-compiler-used-global-variable ↩