diff --git a/compiler-rt/cmake/Modules/AddCompilerRT.cmake b/compiler-rt/cmake/Modules/AddCompilerRT.cmake
index 9c9d256a58b61..4d9b68a3cc25b 100644
--- a/compiler-rt/cmake/Modules/AddCompilerRT.cmake
+++ b/compiler-rt/cmake/Modules/AddCompilerRT.cmake
@@ -643,6 +643,7 @@ macro(add_custom_libcxx name prefix)
     CMAKE_STRIP
     CMAKE_READELF
     CMAKE_SYSROOT
+    CMAKE_TOOLCHAIN_FILE
     LIBCXX_HAS_MUSL_LIBC
     LIBCXX_HAS_GCC_S_LIB
     LIBCXX_HAS_PTHREAD_LIB