WIP raspberry pi cross compiler

Author: nycrat

environment_setup/util.sh

@@ -37,15 +37,10 @@ install_clang_format() {
 }
 
 install_cross_compiler() {
-    file_name=aarch64-tbots-linux-gnu-for-aarch64
     if is_darwin $1; then
-       full_file_name=$file_name.tar.xz
-       curl -L "https://raw.githubusercontent.com/UBC-Thunderbots/Software-External-Dependencies/refs/heads/main/toolchain/$full_file_name" \
-           -o /tmp/tbots_download_cache/$full_file_name
-       tar -xf /tmp/tbots_download_cache/$full_file_name -C /tmp/tbots_download_cache/
-       sudo mv /tmp/tbots_download_cache/aarch64-tbots-linux-gnu /opt/tbotspython
-       rm /tmp/tbots_download_cache/$full_file_name
+        brew install messense/macos-cross-toolchains/aarch64-unknown-linux-gnu
     else
+        file_name=aarch64-tbots-linux-gnu-for-aarch64
         if is_x86 $1; then
             file_name=aarch64-tbots-linux-gnu-for-x86
         fi

src/MODULE.bazel

@@ -250,6 +250,7 @@ register_toolchains(
 )
 
 register_toolchains(
+    "//toolchains/cc:cc_toolchain_for_macos_robot",
     "//toolchains/cc:cc_toolchain_for_k8_aarch64_linux",
     "//toolchains/cc:cc_toolchain_for_k8",
     "//toolchains/cc:cc_toolchain_for_aarch64",
@@ -286,6 +287,12 @@ new_local_repository(
     path = "/opt/tbotspython/aarch64-tbots-linux-gnu/",
 )
 
+new_local_repository(
+    name = "macos_robot_gcc",
+    build_file = "@//extlibs:macos_robot_gcc.BUILD",
+    path = "/opt/homebrew/Cellar/aarch64-unknown-linux-gnu/15.2.0/toolchain/",
+)
+
 new_local_repository(
     name = "motor_board_gcc",
     build_file = "@//extlibs:motor_board_gcc.BUILD",

src/toolchains/cc/BUILD

@@ -269,6 +269,9 @@ cc_toolchain_config_k8_aarch64_linux(
 
 toolchain(
     name = "cc_toolchain_for_k8_aarch64_linux",
+    exec_compatible_with = [
+        "@platforms//os:linux",
+    ],
     target_compatible_with = [
         "@platforms//cpu:aarch64",
         "@platforms//os:linux",
@@ -278,6 +281,77 @@ toolchain(
     toolchain_type = "@bazel_tools//tools/cpp:toolchain_type",
 )
 
+# NOTE: the Cellar path is version-pinned; a repository rule should derive it
+# (e.g. from `brew --prefix`) once this is productionized.
+MACOS_ROBOT_TC = "/opt/homebrew/Cellar/aarch64-unknown-linux-gnu/15.2.0/toolchain"
+
+cc_toolchain_config_k8_aarch64_linux(
+    name = "gcc_macos_robot",
+    builtin_include_directories = [
+        MACOS_ROBOT_TC + "/aarch64-unknown-linux-gnu/include/c++/15.2.0",
+        MACOS_ROBOT_TC + "/aarch64-unknown-linux-gnu/include/c++/15.2.0/aarch64-unknown-linux-gnu",
+        MACOS_ROBOT_TC + "/aarch64-unknown-linux-gnu/include/c++/15.2.0/backward",
+        MACOS_ROBOT_TC + "/lib/gcc/aarch64-unknown-linux-gnu/15.2.0/include",
+        MACOS_ROBOT_TC + "/lib/gcc/aarch64-unknown-linux-gnu/15.2.0/include-fixed",
+        MACOS_ROBOT_TC + "/aarch64-unknown-linux-gnu/include",
+        MACOS_ROBOT_TC + "/aarch64-unknown-linux-gnu/sysroot/usr/include",
+    ] + make_builtin_include_directories(),
+    tool_paths = {
+        "ar": MACOS_ROBOT_TC + "/bin/aarch64-unknown-linux-gnu-ar",
+        "cpp": MACOS_ROBOT_TC + "/bin/aarch64-unknown-linux-gnu-cpp",
+        # messense ships no dwp; point at gcc (unused without fission).
+        "dwp": MACOS_ROBOT_TC + "/bin/aarch64-unknown-linux-gnu-gcc",
+        # wrapper forces -fuse-ld=bfd (messense has no gold linker).
+        "gcc": "wrapper/macos_robot_gcc",
+        "gcov": MACOS_ROBOT_TC + "/bin/aarch64-unknown-linux-gnu-gcov",
+        "ld": MACOS_ROBOT_TC + "/bin/aarch64-unknown-linux-gnu-ld",
+        "nm": MACOS_ROBOT_TC + "/bin/aarch64-unknown-linux-gnu-nm",
+        "objcopy": MACOS_ROBOT_TC + "/bin/aarch64-unknown-linux-gnu-objcopy",
+        "objdump": MACOS_ROBOT_TC + "/bin/aarch64-unknown-linux-gnu-objdump",
+        "strip": MACOS_ROBOT_TC + "/bin/aarch64-unknown-linux-gnu-strip",
+    },
+    toolchain_identifier = "gcc-macos-robot",
+)
+
+filegroup(
+    name = "macos_robot_everything",
+    srcs = [
+        "wrapper/macos_robot_gcc",
+        "@macos_robot_gcc//:everything",
+    ],
+)
+
+cc_toolchain(
+    name = "cc_toolchain_macos_robot",
+    all_files = ":macos_robot_everything",
+    ar_files = ":macos_robot_everything",
+    as_files = ":macos_robot_everything",
+    compiler_files = ":macos_robot_everything",
+    dwp_files = ":macos_robot_everything",
+    linker_files = ":macos_robot_everything",
+    objcopy_files = ":macos_robot_everything",
+    strip_files = ":macos_robot_everything",
+    supports_param_files = 0,
+    tags = ["no-ide"],
+    toolchain_config = ":gcc_macos_robot",
+    toolchain_identifier = "gcc-macos-robot",
+)
+
+toolchain(
+    name = "cc_toolchain_for_macos_robot",
+    exec_compatible_with = [
+        "@platforms//os:osx",
+        "@platforms//cpu:aarch64",
+    ],
+    target_compatible_with = [
+        "@platforms//cpu:aarch64",
+        "@platforms//os:linux",
+        ":glibc_2_27",
+    ],
+    toolchain = ":cc_toolchain_macos_robot",
+    toolchain_type = "@bazel_tools//tools/cpp:toolchain_type",
+)
+
 toolchain(
     name = "cc_toolchain_for_k8",
     exec_compatible_with = [

src/toolchains/cc/wrapper/macos_robot_gcc

@@ -0,0 +1,7 @@
+#!/bin/bash --norc
+
+# The prebuilt messense aarch64-unknown-linux-gnu toolchain ships only the BFD
+# linker (ld/ld.bfd) — no ld.gold. The shared cc_toolchain config adds
+# -fuse-ld=gold, so append -fuse-ld=bfd (last one wins) to use the linker that
+# actually exists. Ignored for non-link (compile) invocations.
+exec /opt/homebrew/Cellar/aarch64-unknown-linux-gnu/15.2.0/toolchain/bin/aarch64-unknown-linux-gnu-gcc "$@" -fuse-ld=bfd