cmd.arg("-C").arg(format!("debug-assertions={}", debug_assertions));
}
- // Build `compiler_builtins` with `-Z emit-stack-sizes` to add stack usage information.
+ // Build all crates in the `std` facade with `-Z emit-stack-sizes` to add stack usage
+ // information.
//
- // When you use this flag with Cargo you get stack usage information on all crates compiled
- // from source, and when you are using LTO you also get information on pre-compiled crates
- // like `core` and `std`. However, there's an exception: `compiler_builtins`. This crate
- // is special and doesn't participate in LTO because it's always linked as a separate object
- // file. Due to this it's impossible to get information about this crate using `RUSTFLAGS`
- // + Cargo, or `cargo rustc`.
+ // When you use this `-Z` flag with Cargo you get stack usage information on all crates
+ // compiled from source, and when you are using LTO you also get information on pre-compiled
+ // crates like `core` and `std`, even if they were not compiled with `-Z emit-stack-sizes`.
+ // However, there's an exception: `compiler_builtins`. This crate is special and doesn't
+ // participate in LTO because it's always linked as a separate object file. For this reason
+ // it's impossible to get stack usage information about `compiler-builtins` using
+ // `RUSTFLAGS` + Cargo, or `cargo rustc`.
//
- // To make the stack usage information of this crate available to Cargo based stack usage
- // analysis tools we compile `compiler_builtins` with the `-Z emit-stack-sizes` flag. The
- // flag is known to currently work with targets that produce ELF files so we limit the use
- // of the flag to those targets.
+ // To make the stack usage information of all crates under the `std` facade available to
+ // Cargo based stack usage analysis tools, in both LTO and non-LTO mode, we compile them
+ // with the `-Z emit-stack-sizes` flag. The `RUSTC_EMIT_STACK_SIZES` var helps us apply this
+ // flag only to the crates in the `std` facade. The `-Z` flag is known to currently work
+ // with targets that produce ELF files so we limit its use flag to those targets.
//
// NOTE(japaric) if this ever causes problem with an LLVM upgrade or any PR feel free to
// remove it or comment it out
- if crate_name == "compiler_builtins"
+ if env::var_os("RUSTC_EMIT_STACK_SIZES").is_some()
&& (target.contains("-linux-")
|| target.contains("-none-eabi")
|| target.ends_with("-none-elf"))
{
- cmd.arg("-Z").arg("emit-stack-sizes");
+ cmd.arg("-Zemit-stack-sizes");
}
if let Ok(s) = env::var("RUSTC_CODEGEN_UNITS") {
let _folder = builder.fold_output(|| format!("stage{}-std", compiler.stage));
builder.info(&format!("Building stage{} std artifacts ({} -> {})", compiler.stage,
&compiler.host, target));
+ // compile with `-Z emit-stack-sizes`; see bootstrap/src/rustc.rs for more details
+ cargo.env("RUSTC_EMIT_STACK_SIZES", "1");
run_cargo(builder,
&mut cargo,
&libstd_stamp(builder, compiler, target),
let _folder = builder.fold_output(|| format!("stage{}-test", compiler.stage));
builder.info(&format!("Building stage{} test artifacts ({} -> {})", compiler.stage,
&compiler.host, target));
+ // compile with `-Z emit-stack-sizes`; see bootstrap/src/rustc.rs for more details
+ cargo.env("RUSTC_EMIT_STACK_SIZES", "1");
run_cargo(builder,
&mut cargo,
&libtest_stamp(builder, compiler, target),