commit: 375da3684e685c6fd8367ffcf37e090526d55e4d
Author: James Le Cuirot <chewi <AT> gentoo <DOT> org>
AuthorDate: Fri May 31 21:49:47 2024 +0000
Commit: James Le Cuirot <chewi <AT> gentoo <DOT> org>
CommitDate: Wed Jun 12 13:18:01 2024 +0000
URL: https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=375da368
cargo.eclass: Enable cross-compiling by setting environment variables
CARGO_BUILD_TARGET and CARGO_TARGET_<triple>_LINKER are enough for pure
Rust. The linker otherwise defaults to `cc`. This doesn't respect any
linker specified in LDFLAGS, but this is also true for native builds. We
would need to do something with RUSTFLAGS.
The HOST_* variables are for the cc-rs crate, which is often used to
build non-Rust code. It uses the usual variables (CC, CFLAGS, etc) for
the target.
Signed-off-by: James Le Cuirot <chewi <AT> gentoo.org>
eclass/cargo.eclass | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)
diff --git a/eclass/cargo.eclass b/eclass/cargo.eclass
index 72c740cda906..40d98211ce7f 100644
--- a/eclass/cargo.eclass
+++ b/eclass/cargo.eclass
@@ -34,7 +34,7 @@ case ${EAPI} in
;;
esac
-inherit flag-o-matic multiprocessing toolchain-funcs
+inherit flag-o-matic multiprocessing rust-toolchain toolchain-funcs
[[ ! ${CARGO_OPTIONAL} ]] && BDEPEND="${RUST_DEPEND}"
@@ -525,6 +525,21 @@ cargo_src_compile() {
filter-lto
tc-export AR CC CXX PKG_CONFIG
+ if tc-is-cross-compiler; then
+ export CARGO_BUILD_TARGET=$(rust_abi)
+ local TRIPLE=${CARGO_BUILD_TARGET//-/_}
+ export CARGO_TARGET_"${TRIPLE^^}"_LINKER=$(tc-getCC)
+
+ # Set vars for cc-rs crate.
+ tc-export_build_env
+ export \
+ HOST_AR=$(tc-getBUILD_AR)
+ HOST_CC=$(tc-getBUILD_CC)
+ HOST_CXX=$(tc-getBUILD_CXX)
+ HOST_CFLAGS=${BUILD_CFLAGS}
+ HOST_CXXFLAGS=${BUILD_CXXFLAGS}
+ fi
+
set -- cargo build $(usex debug "" --release) ${ECARGO_ARGS[@]} "$@"
einfo "${@}"
"${@}" || die "cargo build failed"
