[PATCH v2 1/3] rust-cross-canadian: install target-specific env scripts and fix rustlib lookup

[PATCH v2 1/3] rust-cross-canadian: install target-specific env scripts and fix rustlib lookup

[Harish.Sadineni]

From: Harish Sadineni <Harish.Sadineni@windriver.com>

YOCTO [#15061]

Fixes 32-bit Cargo build failures when using multilib-enabled SDKs.

Store the generated environment setup script in a target-specific
subdirectory so that sourcing the SDK environment always loads the
matching script for the selected target, avoiding accidental reuse of
the 64-bit configuration when building for a 32-bit target.

Also update `CARGO_TARGET_<TRIPLE>_RUSTFLAGS` to add an explicit
`-L` search path to the target `rustlib` directory inside the sysroot.
This ensures Cargo can locate the correct target-specific Rust libraries
during cross-compilation with the cross-canadian toolchain.

Signed-off-by: Harish Sadineni <Harish.Sadineni@windriver.com>
---
 meta/recipes-devtools/rust/rust-cross-canadian.inc | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/meta/recipes-devtools/rust/rust-cross-canadian.inc b/meta/recipes-devtools/rust/rust-cross-canadian.inc
index f083bcda82..bdc63e221f 100644
--- a/meta/recipes-devtools/rust/rust-cross-canadian.inc
+++ b/meta/recipes-devtools/rust/rust-cross-canadian.inc
@@ -51,15 +51,17 @@ do_install () {
     chmod +x "$outfile"
     create_sdk_wrapper "${SYS_BINDIR}/target-rust-ccld-wrapper" "CC"
 
-    ENV_SETUP_DIR=${D}${base_prefix}/environment-setup.d
-    mkdir "${ENV_SETUP_DIR}"
+    ENV_SETUP_DIR=${D}${base_prefix}/environment-setup.d/${TARGET_SYS}
+    mkdir -p "${ENV_SETUP_DIR}"
     RUST_ENV_SETUP_SH="${ENV_SETUP_DIR}/${RUST_TARGET_SYS}_rust.sh"
 
     RUST_TARGET_TRIPLE=`echo ${RUST_TARGET_SYS} | tr '[:lower:]' '[:upper:]' | sed 's/-/_/g'`
 
     cat <<- EOF > "${RUST_ENV_SETUP_SH}"
-	export CARGO_TARGET_${RUST_TARGET_TRIPLE}_RUSTFLAGS="--sysroot=\$OECORE_TARGET_SYSROOT/usr -C link-arg=--sysroot=\$OECORE_TARGET_SYSROOT"
-	export CARGO_BUILD_TARGET="${RUST_TARGET_SYS}"
+	export RUST_TARGET_SYS_VALUE="${RUST_TARGET_SYS}"
+	LIB_PATH="\$OECORE_TARGET_SYSROOT/usr/${baselib}/rustlib/${RUST_TARGET_SYS}/lib"
+	export CARGO_TARGET_${RUST_TARGET_TRIPLE}_RUSTFLAGS="--sysroot=\$OECORE_TARGET_SYSROOT/usr -C link-arg=--sysroot=\$OECORE_TARGET_SYSROOT -L \$LIB_PATH"
+        export CARGO_BUILD_TARGET="${RUST_TARGET_SYS}"
 	export RUST_TARGET_PATH="\$OECORE_NATIVE_SYSROOT/usr/lib/${TARGET_SYS}/rustlib"
 	EOF
 
-- 
2.51.0

[PATCH v2 2/3] toolchain-scripts: source target-specific environment setup scripts

[Harish.Sadineni]

From: Harish Sadineni <Harish.Sadineni@windriver.com>

YOCTO [#15061]

Export `OECORE_TARGET_SYS` in the generated SDK and tree environment
setup scripts, and source any `*.sh` files from
`environment-setup.d/${TARGET_SYS}` in addition to the existing
`environment-setup.d` directory.

This complements the rust-cross-canadian changes, where Rust
environment setup scripts are installed under a target-specific
directory. By sourcing only the scripts that match the active target,
the SDK avoids loading environment settings for other target variants,
such as mixing 32-bit and 64-bit configurations in multilib SDKs.

Signed-off-by: Harish Sadineni <Harish.Sadineni@windriver.com>
---
 meta/classes-recipe/toolchain-scripts.bbclass | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/meta/classes-recipe/toolchain-scripts.bbclass b/meta/classes-recipe/toolchain-scripts.bbclass
index d94dcdee39..f0f599959d 100644
--- a/meta/classes-recipe/toolchain-scripts.bbclass
+++ b/meta/classes-recipe/toolchain-scripts.bbclass
@@ -76,6 +76,7 @@ toolchain_create_sdk_env_script () {
 	echo 'export OECORE_MESON_HOST_CPU_FAMILY="${@meson_cpu_family('TARGET_ARCH', d)}"' >>$script
 	echo 'export OECORE_MESON_HOST_CPU="${TARGET_ARCH}"' >>$script
 	echo 'export OECORE_MESON_HOST_ENDIAN="${@meson_endian('TARGET', d)}"' >>$script
+	echo 'export OECORE_TARGET_SYS="${TARGET_SYS}"' >> $script
 
 	echo 'unset command_not_found_handle' >> $script
 
@@ -110,6 +111,7 @@ toolchain_create_tree_env_script () {
 	echo 'export OECORE_MESON_HOST_CPU_FAMILY="${@meson_cpu_family('TARGET_ARCH', d)}"' >>$script
 	echo 'export OECORE_MESON_HOST_CPU="${TARGET_ARCH}"' >>$script
 	echo 'export OECORE_MESON_HOST_ENDIAN="${@meson_endian('TARGET', d)}"' >>$script
+        echo 'export OECORE_TARGET_SYS="${TARGET_SYS}"' >> $script
 
 	toolchain_shared_env_script
 
@@ -172,6 +174,12 @@ if [ -d "\$OECORE_NATIVE_SYSROOT/environment-setup.d" ]; then
 	    . \$envfile
     done
 fi
+if [ -d "\$OECORE_NATIVE_SYSROOT/environment-setup.d/\$OECORE_TARGET_SYS" ]; then
+    for envfile in \$OECORE_NATIVE_SYSROOT/environment-setup.d/\$OECORE_TARGET_SYS/*.sh; do
+            . \$envfile
+    done
+fi
+
 EOF
 }
 
-- 
2.51.0

[PATCH v2 3/3] oeqa/sdk/cases/rust.py: Expand test to verify cargo build builds for target

[Harish.Sadineni]

From: Harish Sadineni <Harish.Sadineni@windriver.com>

Ensure that cargo build successfully builds the binary for the target by default.
This test validates whether the default build process produces the expected output
for the specified target.

Signed-off-by: Harish Sadineni <Harish.Sadineni@windriver.com>
---
 meta/lib/oeqa/sdk/cases/rust.py | 37 ++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/meta/lib/oeqa/sdk/cases/rust.py b/meta/lib/oeqa/sdk/cases/rust.py
index 4b115bebf5..4802a714ab 100644
--- a/meta/lib/oeqa/sdk/cases/rust.py
+++ b/meta/lib/oeqa/sdk/cases/rust.py
@@ -7,6 +7,10 @@
 import os
 import shutil
 import unittest
+import json
+import subprocess
+import re
+
 
 from oeqa.sdk.case import OESDKTestCase
 
@@ -32,8 +36,39 @@ class RustCompileTest(OESDKTestCase):
 
     def test_cargo_build(self):
         self._run('cd %s/hello; cargo add zstd' % (self.tc.sdk_dir))
-        self._run('cd %s/hello; cargo build' % self.tc.sdk_dir)
+        result_env = self._run("echo $RUST_TARGET_SYS_VALUE")
+        rust_target_sys = result_env.strip()
+        result = self._run(
+            "cd %s/hello; cargo build --message-format=json-render-diagnostics"
+            % self.tc.sdk_dir
+        )
+
+        executable_path = None
+        for line in result.splitlines():
+            try:
+                msg = json.loads(line)
+            except json.JSONDecodeError:
+                continue
+
+            # Cargo emits multiple JSON messages; we want the executable
+            if isinstance(msg, dict) and msg.get("executable"):
+                executable_path = msg["executable"]
+
+        parts = executable_path.split(os.sep)
+        target_index = parts.index("target")
+        path_component = parts[target_index + 1]
+        if path_component in ("debug", "release"):
+            file_output = subprocess.check_output(["file", executable_path]).decode().strip()
+            match = re.search(r"/sysroots/([^/]+)/lib/", file_output)
+            target_triple = match.group(1) if match else None
+        else:
+            target_triple = path_component
 
+        self.assertTrue(
+            rust_target_sys == target_triple,
+            f"Cargo built natively for the nativesdk host instead of '{rust_target_sys}.\n"
+            f"Cargo build needs to build for target by default not nativesdk_host"
+        )
 class RustHostCompileTest(OESDKTestCase):
     td_vars = ['MACHINE', 'SDK_SYS']
 
-- 
2.51.0

Re: [OE-core] [PATCH v2 1/3] rust-cross-canadian: install target-specific env scripts and fix rustlib lookup

[Richard Purdie]

On Fri, 2026-08-07 at 02:31 -0700, Sadineni, Harish via lists.openembedded.org wrote:
> From: Harish Sadineni <Harish.Sadineni@windriver.com>
> 
> YOCTO [#15061]
> 
> Fixes 32-bit Cargo build failures when using multilib-enabled SDKs.
> 
> Store the generated environment setup script in a target-specific
> subdirectory so that sourcing the SDK environment always loads the
> matching script for the selected target, avoiding accidental reuse of
> the 64-bit configuration when building for a 32-bit target.
> 
> Also update `CARGO_TARGET_<TRIPLE>_RUSTFLAGS` to add an explicit
> `-L` search path to the target `rustlib` directory inside the sysroot.
> This ensures Cargo can locate the correct target-specific Rust libraries
> during cross-compilation with the cross-canadian toolchain.
> 
> Signed-off-by: Harish Sadineni <Harish.Sadineni@windriver.com>
> ---
>  meta/recipes-devtools/rust/rust-cross-canadian.inc | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/meta/recipes-devtools/rust/rust-cross-canadian.inc b/meta/recipes-devtools/rust/rust-cross-canadian.inc
> index f083bcda82..bdc63e221f 100644
> --- a/meta/recipes-devtools/rust/rust-cross-canadian.inc
> +++ b/meta/recipes-devtools/rust/rust-cross-canadian.inc
> @@ -51,15 +51,17 @@ do_install () {
>      chmod +x "$outfile"
>      create_sdk_wrapper "${SYS_BINDIR}/target-rust-ccld-wrapper" "CC"
>  
> -    ENV_SETUP_DIR=${D}${base_prefix}/environment-setup.d
> -    mkdir "${ENV_SETUP_DIR}"
> +    ENV_SETUP_DIR=${D}${base_prefix}/environment-setup.d/${TARGET_SYS}
> +    mkdir -p "${ENV_SETUP_DIR}"
>      RUST_ENV_SETUP_SH="${ENV_SETUP_DIR}/${RUST_TARGET_SYS}_rust.sh"
>  
>      RUST_TARGET_TRIPLE=`echo ${RUST_TARGET_SYS} | tr '[:lower:]' '[:upper:]' | sed 's/-/_/g'`
>  
>      cat <<- EOF > "${RUST_ENV_SETUP_SH}"
> -	export CARGO_TARGET_${RUST_TARGET_TRIPLE}_RUSTFLAGS="--sysroot=\$OECORE_TARGET_SYSROOT/usr -C link-arg=--sysroot=\$OECORE_TARGET_SYSROOT"
> -	export CARGO_BUILD_TARGET="${RUST_TARGET_SYS}"
> +	export RUST_TARGET_SYS_VALUE="${RUST_TARGET_SYS}"
> +	LIB_PATH="\$OECORE_TARGET_SYSROOT/usr/${baselib}/rustlib/${RUST_TARGET_SYS}/lib"
> +	export CARGO_TARGET_${RUST_TARGET_TRIPLE}_RUSTFLAGS="--sysroot=\$OECORE_TARGET_SYSROOT/usr -C link-arg=--sysroot=\$OECORE_TARGET_SYSROOT -L \$LIB_PATH"
> +        export CARGO_BUILD_TARGET="${RUST_TARGET_SYS}"
>  	export RUST_TARGET_PATH="\$OECORE_NATIVE_SYSROOT/usr/lib/${TARGET_SYS}/rustlib"
>  	EOF

I'm a bit confused here. The script in question already has
${RUST_TARGET_SYS} in its name, so it is already target specific. Why
do we need to move it to a target specific directory?

Cheers,

Richard