diff --git a/pkgs/development/compilers/llvm/common.nix b/pkgs/development/compilers/llvm/common.nix
index e4f55963a6f..27f48ff3f11 100644
--- a/pkgs/development/compilers/llvm/common.nix
+++ b/pkgs/development/compilers/llvm/common.nix
@@ -2,7 +2,9 @@
 
 rec {
   llvmBackend = platform:
-    if platform.parsed.cpu.family == "x86" then
+    if builtins.typeOf platform == "string" then
+      platform
+    else if platform.parsed.cpu.family == "x86" then
       "X86"
     else if platform.parsed.cpu.name == "aarch64" then
       "AArch64"