--- build/config/rust.gni.orig	2022-02-07 13:39:41 UTC
+++ build/config/rust.gni
@@ -84,7 +84,7 @@ if (enable_rust) {
     rust_sysroot = get_path_info(rust_sysroot_absolute, "abspath")
     use_unverified_rust_toolchain = true
   } else {
-    if (host_os != "linux") {
+    if (host_os != "linux" && host_os != "openbsd" && host_os != "freebsd") {
       assert(
           false,
           "Attempt to use standard Rust toolchain on an unsupported platform")