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Prefer doc comments over //-comments in compiler

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Maybe Waffle 2022-11-27 11:15:06 +00:00
parent 0e9eee6811
commit 1d42936b18
83 changed files with 400 additions and 387 deletions
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64
compiler/rustc_codegen_ssa/src/back/metadata.rs
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@ -191,38 +191,38 @@ pub enum MetadataPosition {
Last,
}
// For rlibs we "pack" rustc metadata into a dummy object file.
//
// Historically it was needed because rustc linked rlibs as whole-archive in some cases.
// In that case linkers try to include all files located in an archive, so if metadata is stored
// in an archive then it needs to be of a form that the linker is able to process.
// Now it's not clear whether metadata still needs to be wrapped into an object file or not.
//
// Note, though, that we don't actually want this metadata to show up in any
// final output of the compiler. Instead this is purely for rustc's own
// metadata tracking purposes.
//
// With the above in mind, each "flavor" of object format gets special
// handling here depending on the target:
//
// * MachO - macos-like targets will insert the metadata into a section that
// is sort of fake dwarf debug info. Inspecting the source of the macos
// linker this causes these sections to be skipped automatically because
// it's not in an allowlist of otherwise well known dwarf section names to
// go into the final artifact.
//
// * WebAssembly - we actually don't have any container format for this
// target. WebAssembly doesn't support the `dylib` crate type anyway so
// there's no need for us to support this at this time. Consequently the
// metadata bytes are simply stored as-is into an rlib.
//
// * COFF - Windows-like targets create an object with a section that has
// the `IMAGE_SCN_LNK_REMOVE` flag set which ensures that if the linker
// ever sees the section it doesn't process it and it's removed.
//
// * ELF - All other targets are similar to Windows in that there's a
// `SHF_EXCLUDE` flag we can set on sections in an object file to get
// automatically removed from the final output.
/// For rlibs we "pack" rustc metadata into a dummy object file.
///
/// Historically it was needed because rustc linked rlibs as whole-archive in some cases.
/// In that case linkers try to include all files located in an archive, so if metadata is stored
/// in an archive then it needs to be of a form that the linker is able to process.
/// Now it's not clear whether metadata still needs to be wrapped into an object file or not.
///
/// Note, though, that we don't actually want this metadata to show up in any
/// final output of the compiler. Instead this is purely for rustc's own
/// metadata tracking purposes.
///
/// With the above in mind, each "flavor" of object format gets special
/// handling here depending on the target:
///
/// * MachO - macos-like targets will insert the metadata into a section that
/// is sort of fake dwarf debug info. Inspecting the source of the macos
/// linker this causes these sections to be skipped automatically because
/// it's not in an allowlist of otherwise well known dwarf section names to
/// go into the final artifact.
///
/// * WebAssembly - we actually don't have any container format for this
/// target. WebAssembly doesn't support the `dylib` crate type anyway so
/// there's no need for us to support this at this time. Consequently the
/// metadata bytes are simply stored as-is into an rlib.
///
/// * COFF - Windows-like targets create an object with a section that has
/// the `IMAGE_SCN_LNK_REMOVE` flag set which ensures that if the linker
/// ever sees the section it doesn't process it and it's removed.
///
/// * ELF - All other targets are similar to Windows in that there's a
/// `SHF_EXCLUDE` flag we can set on sections in an object file to get
/// automatically removed from the final output.
pub fn create_wrapper_file(
sess: &Session,
section_name: Vec<u8>,