diff --git a/pkgs/development/compilers/llvm/7/llvm.nix b/pkgs/development/compilers/llvm/7/llvm.nix
index 67bde813feed..06024856356f 100644
--- a/pkgs/development/compilers/llvm/7/llvm.nix
+++ b/pkgs/development/compilers/llvm/7/llvm.nix
@@ -23,6 +23,18 @@ let
   # Used when creating a version-suffixed symlink of libLLVM.dylib
   shortVersion = with stdenv.lib;
     concatStringsSep "." (take 1 (splitString "." release_version));
+
+  llvmTarget = platform:
+    if platform.parsed.cpu.family == "x86" then
+      "X86"
+    else if platform.parsed.cpu.name == "aarch64" then
+      "AArch64"
+    else if platform.parsed.cpu.family == "arm" then
+      "ARM"
+    else if platform.parsed.cpu.family == "mips" then
+      "Mips"
+    else
+      throw "Unsupported system";
 in stdenv.mkDerivation (rec {
   name = "llvm-${version}";
 
@@ -78,10 +90,9 @@ in stdenv.mkDerivation (rec {
     "-DLLVM_BUILD_TESTS=ON"
     "-DLLVM_ENABLE_FFI=ON"
     "-DLLVM_ENABLE_RTTI=ON"
-
     "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
-    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
-    "-DTARGET_TRIPLE=${stdenv.hostPlatform.config}"
+    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.targetPlatform.config}"
+    "-DLLVM_TARGETS_TO_BUILD=${llvmTarget stdenv.hostPlatform};${llvmTarget stdenv.targetPlatform}"
 
     "-DLLVM_ENABLE_DUMP=ON"
   ]