From d1cea1ef444a7f99852d2f707ab1dd128c3685ed Mon Sep 17 00:00:00 2001
From: Brian Granaghan <granaghan@google.com>
Date: Wed, 23 Aug 2023 19:30:57 +0000
Subject: [PATCH] Add TemplateVariableInfo for build script toolchains
 attribute.

---
 cargo/private/cargo_build_script.bzl | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/cargo/private/cargo_build_script.bzl b/cargo/private/cargo_build_script.bzl
index e567c1c5cf..85ed019297 100644
--- a/cargo/private/cargo_build_script.bzl
+++ b/cargo/private/cargo_build_script.bzl
@@ -187,6 +187,9 @@ def _cargo_build_script_impl(ctx):
             if type(all_files) == "list":
                 all_files = depset(all_files)
             toolchain_tools.append(all_files)
+        if platform_common.TemplateVariableInfo in target:
+            variables = getattr(target[platform_common.TemplateVariableInfo], "variables", depset([]))
+            env.update(variables)
 
     _merge_env_dict(env, expand_dict_value_locations(
         ctx,