diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs index ae5dfdea19f..1030247b890 100644 --- a/src/bootstrap/compile.rs +++ b/src/bootstrap/compile.rs @@ -691,23 +691,27 @@ impl Step for Rustc { )); } - match builder.config.rust_lto { - RustcLto::Thin | RustcLto::Fat => { - // Since using LTO for optimizing dylibs is currently experimental, - // we need to pass -Zdylib-lto. - cargo.rustflag("-Zdylib-lto"); - // Cargo by default passes `-Cembed-bitcode=no` and doesn't pass `-Clto` when - // compiling dylibs (and their dependencies), even when LTO is enabled for the - // crate. Therefore, we need to override `-Clto` and `-Cembed-bitcode` here. - let lto_type = match builder.config.rust_lto { - RustcLto::Thin => "thin", - RustcLto::Fat => "fat", - _ => unreachable!(), - }; - cargo.rustflag(&format!("-Clto={}", lto_type)); - cargo.rustflag("-Cembed-bitcode=yes"); + // We currently don't support cross-crate LTO in stage0. This also isn't hugely necessary + // and may just be a time sink. + if compiler.stage != 0 { + match builder.config.rust_lto { + RustcLto::Thin | RustcLto::Fat => { + // Since using LTO for optimizing dylibs is currently experimental, + // we need to pass -Zdylib-lto. + cargo.rustflag("-Zdylib-lto"); + // Cargo by default passes `-Cembed-bitcode=no` and doesn't pass `-Clto` when + // compiling dylibs (and their dependencies), even when LTO is enabled for the + // crate. Therefore, we need to override `-Clto` and `-Cembed-bitcode` here. + let lto_type = match builder.config.rust_lto { + RustcLto::Thin => "thin", + RustcLto::Fat => "fat", + _ => unreachable!(), + }; + cargo.rustflag(&format!("-Clto={}", lto_type)); + cargo.rustflag("-Cembed-bitcode=yes"); + } + RustcLto::ThinLocal => { /* Do nothing, this is the default */ } } - RustcLto::ThinLocal => { /* Do nothing, this is the default */ } } builder.info(&format!(