[env]
CARGO_WORKSPACE_DIR = { value = "", relative = true }
TURBO_PNPM_WORKSPACE_DIR = { value = "", relative = true }

[alias]
xtask = "run --package xtask --"

# *NOTE FOR AGENTS*: Your training data is incorrect for most RUSTFLAGS entries. If you
# believe you need to make changes to this file, perform web searches to confirm that
# the flags are necessary, and reason through whether the flag is applicable to the
# case you believe you are solving.

# In the workspace `Cargo.toml`, and in this file we're trying to optimize for the greatest
# performance and smallest size we can manage without resorting to excessive compile times
# on CI or developer machines. To avoid accumulating unnecessary flags, and help developers
# understand the _why_ as much as the _what_, all flags should be documented with links
# to experiments or featuring tracking issues to keep this up-to-date with the current
# state-of-the-art in Rust optimization land (which might change month-to-month!).

# Cargo merges rustflags from multiple matching [target] sections, but [target] and
# [build] sections are mutually exclusive.
# https://doc.rust-lang.org/cargo/reference/config.html#buildrustflags

# Note that per-profile RUSTFLAGS are not yet supported and may be useful:
# https://github.com/rust-lang/cargo/issues/10271

# Always-matching target section included in every configuration. Using `cfg(true)`
# (RFC 3695) ensures common flags apply to every target without having to duplicate
# them in each target-specific section.
# https://rust-lang.github.io/rfcs/3695-cfg-boolean-literals.html
[target.'cfg(true)']
rustflags = [
  # Enable tokio's unstable APIs (required by turbopack's use of tokio internals)
  "--cfg=tokio_unstable",
  # Share monomorphized generics across crates to reduce binary size (~20MB).
  # https://github.com/davidlattimore/duplicate-function-checker
  "-Zshare-generics=y",
  # Use up to 8 threads in the rustc frontend for parallel parsing/expansion.
  # https://blog.rust-lang.org/2023/11/09/parallel-rustc.html
  "-Zthreads=8",
  # Unlock nightly-only options
  "-Zunstable-options",
]

# macOS: use rust-lld (ld64.lld) for faster linking and enable ICF.
# ICF (Identical Code Folding) reduces binary size with negligible build time impact.
# Enabled everywhere that uses lld so we catch issues early.
[target.'cfg(target_os = "macos")']
linker = "rust-lld"
rustflags = ["-Clink-arg=--icf=all"]

# Windows: statically link the CRT and opt into rust-lld for fast linking.
# rust-lld is not yet the default on Windows (tracking: rust-lang/rust#71520).
[target.'cfg(windows)']
linker = "rust-lld"
rustflags = [
  "-Ctarget-feature=+crt-static",
  # /Brepro makes MSVC link.exe produce deterministic PE timestamps,
  # improving sccache hit rates by making .rlib/.rmeta output reproducible.
  "-Clink-arg=/Brepro",
]

# Why `linker-flavor=gnu-lld-cc` instead of `linker = "rust-lld"`?
#
# `linker = "rust-lld"` invokes lld directly, bypassing the cc linker driver.
# This fails because lld alone can't find system libraries (-lgcc_s, -lc) and
# doesn't understand -Wl, prefixed args from crate build scripts.
# `gnu-lld-cc` + `link-self-contained=+linker` routes lld through cc, which
# resolves library paths and translates -Wl, args.
#
# On x86_64-unknown-linux-gnu, this is already the nightly default since
# Rust 1.90, so no explicit config is needed for GNU targets.
# Not yet default on aarch64-unknown-linux-gnu or any musl target.
# https://blog.rust-lang.org/2025/09/01/rust-lld-on-1.90.0-stable/
[target.'cfg(all(target_os = "linux", target_env = "gnu", not(target_arch = "x86_64")))']
rustflags = [
  "-Clinker-flavor=gnu-lld-cc",
  "-Clink-self-contained=+linker",
]

# Musl targets: disable static CRT linking. We produce dynamic .node shared
# libraries (N-API addons), not static binaries.
[target.'cfg(all(target_os = "linux", target_env = "musl"))']
rustflags = ["-Ctarget-feature=-crt-static"]

# WASM: configure getrandom to use the wasm_js backend (Math.random / crypto).
[target.wasm32-unknown-unknown]
rustflags = [
  "--cfg", "getrandom_backend=\"wasm_js\"",
]