Implement -Z function-sections=yes|no #78414
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I implemented it as a flag because AFAIK that particular setting doesn't require libstd etc to be built the same thing, thus it is a bit unfortunate that it requires building a whole new target currently to change the value. Plus, it would make it easier to check on Windows if we can turn back |
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@bors delegate=bjorn3 |
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✌️ @bjorn3 can now approve this pull request |
| @@ -904,6 +904,8 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options, | |||
| "force all crates to be `rustc_private` unstable (default: no)"), | |||
| fuel: Option<(String, u64)> = (None, parse_optimization_fuel, [TRACKED], | |||
| "set the optimization fuel quota for a crate"), | |||
| function_sections: Option<bool> = (None, parse_opt_bool, [TRACKED], | |||
| "whether each function should go in its own .text section"), | |||
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.text is not exactly the most portable name (e.g. machO uses __text AFAIR). I suggest dropping the . or perhaps the whole .text.
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That's a good point, I removed it.
This lets rustc users tweak whether all functions should be put in their own TEXT section, using whatever default value the target defines if the flag is missing.
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@bors r=nagisa,bjorn3 |
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📌 Commit 0569422 has been approved by |
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Any chance I could get a |
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Its the next PR in the bors queue. |
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☀️ Test successful - checks-actions |
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This lets rustc users tweak whether all functions should be put in their own TEXT section, using whatever default value the target defines if the flag is missing.
I'm having fun experimenting with musl libc and trying to implement the start symbol in Rust, that means avoiding code that requires relocations, and AFAIK putting everything in its own section makes the toolchain generate
GOTPCRELrelocations for symbols that could use plain old PC-relative addressing (at least onx86_64) if they were all in the same section.