From d7895c2810864934356131ee47de2ba18947c844 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Wed, 13 Jun 2018 16:25:12 -0400
Subject: [PATCH] darwin stdenv: fix llvmPackage overrides

It may seem nice and abstract to just override the default version, but
that breaks the alias relationship where the original llvmPackages_* is
no longer in sync. Put another away, modifying the referee rather
instead of breaking the reference "copy-on-write" is impossible.
---
 pkgs/stdenv/darwin/default.nix | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/pkgs/stdenv/darwin/default.nix b/pkgs/stdenv/darwin/default.nix
index 951c96877f96..57b59f26204c 100644
--- a/pkgs/stdenv/darwin/default.nix
+++ b/pkgs/stdenv/darwin/default.nix
@@ -275,10 +275,9 @@ in rec {
         libcxxabi libcxx ncurses libffi zlib gmp pcre gnugrep
         coreutils findutils diffutils patchutils;
 
-       llvmPackages = let llvmOverride = llvmPackages.llvm.override { inherit libcxxabi; };
-       in super.llvmPackages // {
-         llvm = llvmOverride;
-         clang-unwrapped = llvmPackages.clang-unwrapped.override { llvm = llvmOverride; };
+       llvmPackages_5 = super.llvmPackages_5 // {
+         llvm = llvmPackages_5.llvm.override { inherit libcxxabi; };
+         clang-unwrapped = llvmPackages_5.clang-unwrapped.override { llvm = self.llvmPackages_5.llvm; };
        };
 
       darwin = super.darwin // {
@@ -314,8 +313,8 @@ in rec {
         libcxxabi libcxx ncurses libffi zlib llvm gmp pcre gnugrep
         coreutils findutils diffutils patchutils;
 
-      llvmPackages = super.llvmPackages // {
-        inherit (llvmPackages) llvm clang-unwrapped;
+      llvmPackages_5 = super.llvmPackages_5 // {
+        inherit (llvmPackages_5) llvm clang-unwrapped;
       };
 
       darwin = super.darwin // {