From d417ada9a6b13e4a070dd4eb7309adeb708db432 Mon Sep 17 00:00:00 2001
From: Matthew Bauer <mjbauer95@gmail.com>
Date: Tue, 17 Apr 2018 09:50:21 -0500
Subject: [PATCH] clang: only link if LLVMgold exists

buildEnv now errors with broken symlinks. Lots of things like this
still exist.

Discussion in #39038.

(cherry picked from commit 7b73c7f49a0a4673987b661b9d679ec595704d89)
---
 pkgs/development/compilers/llvm/3.4/clang.nix         | 5 ++++-
 pkgs/development/compilers/llvm/3.5/clang.nix         | 5 ++++-
 pkgs/development/compilers/llvm/3.7/clang/default.nix | 5 ++++-
 pkgs/development/compilers/llvm/3.8/clang/default.nix | 5 ++++-
 pkgs/development/compilers/llvm/3.9/clang/default.nix | 5 ++++-
 pkgs/development/compilers/llvm/4/clang/default.nix   | 5 ++++-
 pkgs/development/compilers/llvm/6/clang/default.nix   | 5 ++++-
 7 files changed, 28 insertions(+), 7 deletions(-)

diff --git a/pkgs/development/compilers/llvm/3.4/clang.nix b/pkgs/development/compilers/llvm/3.4/clang.nix
index 10510c750354..863e7eb22474 100644
--- a/pkgs/development/compilers/llvm/3.4/clang.nix
+++ b/pkgs/development/compilers/llvm/3.4/clang.nix
@@ -29,7 +29,10 @@ stdenv.mkDerivation {
   # Clang expects to find LLVMgold in its own prefix
   # Clang expects to find sanitizer libraries in its own prefix
   postInstall = ''
-    ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+    if [ -e ${llvm}/lib/LLVMgold.so ]; then
+      ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+    fi
+
     ln -sv ${llvm}/lib/clang/${version}/lib $out/lib/clang/${version}/
   '';
 
diff --git a/pkgs/development/compilers/llvm/3.5/clang.nix b/pkgs/development/compilers/llvm/3.5/clang.nix
index f15c989ef510..b61118439ee7 100644
--- a/pkgs/development/compilers/llvm/3.5/clang.nix
+++ b/pkgs/development/compilers/llvm/3.5/clang.nix
@@ -31,7 +31,10 @@ in stdenv.mkDerivation {
   # Clang expects to find LLVMgold in its own prefix
   # Clang expects to find sanitizer libraries in its own prefix
   postInstall = ''
-    ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+    if [ -e ${llvm}/lib/LLVMgold.so ]; then
+      ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+    fi
+
     ln -sv ${llvm}/lib/clang/${version}/lib $out/lib/clang/${version}/
     ln -sv $out/bin/clang $out/bin/cpp
   '';
diff --git a/pkgs/development/compilers/llvm/3.7/clang/default.nix b/pkgs/development/compilers/llvm/3.7/clang/default.nix
index f27e3f0089e2..a63706e95cfb 100644
--- a/pkgs/development/compilers/llvm/3.7/clang/default.nix
+++ b/pkgs/development/compilers/llvm/3.7/clang/default.nix
@@ -32,7 +32,10 @@ let
     # Clang expects to find LLVMgold in its own prefix
     # Clang expects to find sanitizer libraries in its own prefix
     postInstall = ''
-      ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      if [ -e ${llvm}/lib/LLVMgold.so ]; then
+        ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      fi
+
       ln -sv ${llvm}/lib/clang/${version}/lib $out/lib/clang/${version}/
       ln -sv $out/bin/clang $out/bin/cpp
     '';
diff --git a/pkgs/development/compilers/llvm/3.8/clang/default.nix b/pkgs/development/compilers/llvm/3.8/clang/default.nix
index 0147485dd58d..c8b2fec5e51d 100644
--- a/pkgs/development/compilers/llvm/3.8/clang/default.nix
+++ b/pkgs/development/compilers/llvm/3.8/clang/default.nix
@@ -34,7 +34,10 @@ let
     # Clang expects to find LLVMgold in its own prefix
     # Clang expects to find sanitizer libraries in its own prefix
     postInstall = ''
-      ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      if [ -e ${llvm}/lib/LLVMgold.so ]; then
+        ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      fi
+
       ln -sv ${llvm}/lib/clang/${version}/lib $out/lib/clang/${version}/
       ln -sv $out/bin/clang $out/bin/cpp
 
diff --git a/pkgs/development/compilers/llvm/3.9/clang/default.nix b/pkgs/development/compilers/llvm/3.9/clang/default.nix
index aafe30e4c9b3..fabc6a39d9f4 100644
--- a/pkgs/development/compilers/llvm/3.9/clang/default.nix
+++ b/pkgs/development/compilers/llvm/3.9/clang/default.nix
@@ -36,7 +36,10 @@ let
     # Clang expects to find LLVMgold in its own prefix
     # Clang expects to find sanitizer libraries in its own prefix
     postInstall = ''
-      ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      if [ -e ${llvm}/lib/LLVMgold.so ]; then
+        ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      fi
+
       ln -sv ${llvm}/lib/clang/${version}/lib $out/lib/clang/${version}/
       ln -sv $out/bin/clang $out/bin/cpp
 
diff --git a/pkgs/development/compilers/llvm/4/clang/default.nix b/pkgs/development/compilers/llvm/4/clang/default.nix
index 5531fd2ab77e..e8f025c24ede 100644
--- a/pkgs/development/compilers/llvm/4/clang/default.nix
+++ b/pkgs/development/compilers/llvm/4/clang/default.nix
@@ -52,7 +52,10 @@ let
     # Clang expects to find LLVMgold in its own prefix
     # Clang expects to find sanitizer libraries in its own prefix
     postInstall = ''
-      ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      if [ -e ${llvm}/lib/LLVMgold.so ]; then
+        ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      fi
+
       ln -sv ${llvm}/lib/clang/${release_version}/lib $out/lib/clang/${release_version}/
       ln -sv $out/bin/clang $out/bin/cpp
 
diff --git a/pkgs/development/compilers/llvm/6/clang/default.nix b/pkgs/development/compilers/llvm/6/clang/default.nix
index 919efdc8ef97..c540a8267e97 100644
--- a/pkgs/development/compilers/llvm/6/clang/default.nix
+++ b/pkgs/development/compilers/llvm/6/clang/default.nix
@@ -53,7 +53,10 @@ let
     # Clang expects to find LLVMgold in its own prefix
     # Clang expects to find sanitizer libraries in its own prefix
     postInstall = ''
-      ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      if [ -e ${llvm}/lib/LLVMgold.so ]; then
+        ln -sv ${llvm}/lib/LLVMgold.so $out/lib
+      fi
+
       ln -sv ${llvm}/lib/clang/${release_version}/lib $out/lib/clang/${release_version}/
       ln -sv $out/bin/clang $out/bin/cpp