From 55a476b00bac9c5e3d2164b1e9c62f67df3b4a63 Mon Sep 17 00:00:00 2001
From: sternenseemann <0rpkxez4ksa01gb3typccl0i@systemli.org>
Date: Sat, 17 Apr 2021 16:59:35 +0200
Subject: [PATCH] llvmPackages_7.libcxx: make sure to use compiler-rt if
 useLLVM

This reflects what the other llvmPackages sets are doing.
---
 pkgs/development/compilers/llvm/7/libc++/default.nix | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/pkgs/development/compilers/llvm/7/libc++/default.nix b/pkgs/development/compilers/llvm/7/libc++/default.nix
index fb50c4e24d7..37f90fae5e4 100644
--- a/pkgs/development/compilers/llvm/7/libc++/default.nix
+++ b/pkgs/development/compilers/llvm/7/libc++/default.nix
@@ -37,7 +37,8 @@ stdenv.mkDerivation {
     "-DLIBCXX_LIBCPPABI_VERSION=2"
     "-DLIBCXX_CXX_ABI=libcxxabi"
   ] ++ lib.optional stdenv.hostPlatform.isMusl "-DLIBCXX_HAS_MUSL_LIBC=1"
-  ++ lib.optional (!enableShared) "-DLIBCXX_ENABLE_SHARED=OFF" ;
+    ++ lib.optional (stdenv.hostPlatform.useLLVM or false) "-DLIBCXX_USE_COMPILER_RT=ON"
+    ++ lib.optional (!enableShared) "-DLIBCXX_ENABLE_SHARED=OFF" ;
 
   passthru = {
     isLLVM = true;