www-client/chromium: wire-up cross-compile support

Cross-compiling still does not work, but this gets us closer.

- Build GN with the host (CBUILD) compiler, skip rebuild after bootstrap.
- Add a toolchain definition for the host (CBUILD) compiler.
- Set the host_toolchain option.
- Set the target_cpu option based on the target arch (CHOST).

The host_toolchain option is also set for native builds. This makes
clang work without setting clang_base_path.

Package-Manager: Portage-2.3.6_p7, Repoman-2.3.2_p75

1 files changed, 18 insertions, 0 deletions

diff --git a/www-client/chromium/files/toolchain/BUILD.gn b/www-client/chromium/files/toolchain/BUILD.gn
index 78f7b57e3be5..f88d3afdcfda 100644
--- a/www-client/chromium/files/toolchain/BUILD.gn
+++ b/www-client/chromium/files/toolchain/BUILD.gn
@@ -17,3 +17,21 @@ gcc_toolchain("default") {
     current_os = current_os
   }
 }
+
+gcc_toolchain("host") {
+  cc = getenv("BUILD_CC")
+  cxx = getenv("BUILD_CXX")
+  ar = getenv("BUILD_AR")
+  nm = getenv("BUILD_NM")
+  ld = cxx
+
+  extra_cflags = getenv("BUILD_CFLAGS")
+  extra_cppflags = getenv("BUILD_CPPFLAGS")
+  extra_cxxflags = getenv("BUILD_CXXFLAGS")
+  extra_ldflags = getenv("BUILD_LDFLAGS")
+
+  toolchain_args = {
+    current_cpu = current_cpu
+    current_os = current_os
+  }
+}