llvm6: same python output fix from #33871

Unlike that PR, however, this doesn't need to go to staging
since no one depends on a package that doesn't exist yet :).

pkgs/development/compilers/llvm/6/llvm.nix

@@ -38,7 +38,7 @@ in stdenv.mkDerivation (rec {
     mv compiler-rt-* $sourceRoot/projects/compiler-rt
   '';
 
-  outputs = [ "out" ]
+  outputs = [ "out" "python" ]
     ++ stdenv.lib.optional enableSharedLibraries "lib";
 
   nativeBuildInputs = [ perl groff cmake python ]
@@ -120,7 +120,11 @@ in stdenv.mkDerivation (rec {
     export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$PWD/lib
   '';
 
-  postInstall = stdenv.lib.optionalString enableSharedLibraries ''
+  postInstall = ''
+    mkdir -p $python/share
+    mv $out/share/opt-viewer $python/share/opt-viewer
+  ''
+  + stdenv.lib.optionalString enableSharedLibraries ''
     moveToOutput "lib/libLLVM-*" "$lib"
     moveToOutput "lib/libLLVM${stdenv.hostPlatform.extensions.sharedLibrary}" "$lib"
     substituteInPlace "$out/lib/cmake/llvm/LLVMExports-${if debugVersion then "debug" else "release"}.cmake" \