Starting work on full GN build

build/toolchain/linux/BUILD.gn

Index: build/toolchain/linux/BUILD.gn
diff --git a/build/toolchain/linux/BUILD.gn b/build/toolchain/linux/BUILD.gn
index c16e31c46b1924d9cf2707736e0a44bf721329cc..ae090b0fb0e48db0ce42b7587581c4289d031821 100644
--- a/build/toolchain/linux/BUILD.gn
+++ b/build/toolchain/linux/BUILD.gn
@@ -8,6 +8,10 @@ import("//build/toolchain/clang.gni")
 import("//build/toolchain/gcc_toolchain.gni")
 import("//build/toolchain/goma.gni")
 
+declare_args() {
+  toolchain_prefix = ""
+}
+
 if (use_goma) {
   assert(!use_ccache, "Goma and ccache can't be used together.")
   compiler_prefix = "$goma_dir/gomacc "
@@ -31,14 +35,23 @@ gcc_toolchain("arm") {
   is_clang = false
 }
 
+gcc_toolchain("arm64") {
+  cc = "${compiler_prefix}aarch64-linux-gnu-gcc"
+  cxx = "${compiler_prefix}aarch64-linux-gnu-g++"
+
+  ar = "aarch64-linux-gnu-ar"
+  ld = cxx
+  readelf = "aarch64-linux-gnu-readelf"
+  nm = "aarch64-linux-gnu-nm"
+
+  toolchain_cpu = "arm64"
+  toolchain_os = "linux"
+  is_clang = false
+}
+
 gcc_toolchain("clang_x86") {
-  if (use_clang_type_profiler) {
-    prefix = rebase_path("//third_party/llvm-allocated-type/Linux_ia32/bin",
-                         root_build_dir)
-  } else {
-    prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
-                         root_build_dir)
-  }
+  prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
+                       root_build_dir)
   cc = "${compiler_prefix}$prefix/clang"
   cxx = "${compiler_prefix}$prefix/clang++"
   readelf = "readelf"
@@ -53,7 +66,7 @@ gcc_toolchain("clang_x86") {
 
 gcc_toolchain("x86") {
   cc = "${compiler_prefix}gcc"
-  cxx = "$compiler_prefix}g++"
+  cxx = "${compiler_prefix}g++"
 
   readelf = "readelf"
   nm = "nm"
@@ -66,13 +79,8 @@ gcc_toolchain("x86") {
 }
 
 gcc_toolchain("clang_x64") {
-  if (use_clang_type_profiler) {
-    prefix = rebase_path("//third_party/llvm-allocated-type/Linux_x64/bin",
-                         root_build_dir)
-  } else {
-    prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
-                         root_build_dir)
-  }
+  prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
+                       root_build_dir)
   cc = "${compiler_prefix}$prefix/clang"
   cxx = "${compiler_prefix}$prefix/clang++"
 
@@ -102,14 +110,14 @@ gcc_toolchain("x64") {
 }
 
 gcc_toolchain("mipsel") {
-  cc = "mipsel-linux-gnu-gcc"
-  cxx = "mipsel-linux-gnu-g++"
-  ar = "mipsel-linux-gnu-ar"
+  cc = "${toolchain_prefix}gcc"
+  cxx = "${toolchain_prefix}g++"
+  ar = "${toolchain_prefix}ar"
   ld = cxx
-  readelf = "mipsel-linux-gnu-readelf"
-  nm = "mipsel-linux-gnu-nm"
+  readelf = "${toolchain_prefix}readelf"
+  nm = "${toolchain_prefix}nm"
 
-  toolchain_cpu = "mipsel"
+  toolchain_cpu = "${target_cpu}"
   toolchain_os = "linux"
-  is_clang = false
+  is_clang = is_clang
 }