From b5f228c836aa88a73f94e89ef830ad9ad427f56d Mon Sep 17 00:00:00 2001
From: Will Cohen <willcohen@users.noreply.github.com>
Date: Mon, 9 May 2022 10:56:23 -0400
Subject: [PATCH] emscriptenStdenv: fix cache location

---
 pkgs/development/em-modules/generic/default.nix | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/pkgs/development/em-modules/generic/default.nix b/pkgs/development/em-modules/generic/default.nix
index 8bfbf6ec309..a8597202941 100644
--- a/pkgs/development/em-modules/generic/default.nix
+++ b/pkgs/development/em-modules/generic/default.nix
@@ -1,4 +1,4 @@
-{ pkgs, lib, emscripten, python2 }:
+{ pkgs, lib, emscripten, python3 }:
 
 { buildInputs ? [], nativeBuildInputs ? []
 
@@ -12,8 +12,8 @@ pkgs.stdenv.mkDerivation (
 
   pname = "emscripten-${lib.getName args}";
   version = lib.getVersion args;
-  buildInputs = [ emscripten python2 ] ++ buildInputs;
-  nativeBuildInputs = [ emscripten python2 ] ++ nativeBuildInputs;
+  buildInputs = [ emscripten python3 ] ++ buildInputs;
+  nativeBuildInputs = [ emscripten python3 ] ++ nativeBuildInputs;
 
   # fake conftest results with emscripten's python magic
   EMCONFIGURE_JS=2;
@@ -25,6 +25,9 @@ pkgs.stdenv.mkDerivation (
 
     emconfigure ./configure --prefix=$out
 
+    mkdir -p .emscriptencache
+    export EM_CACHE=$(pwd)/.emscriptencache
+
     runHook postConfigure
   '';
 
@@ -32,6 +35,7 @@ pkgs.stdenv.mkDerivation (
     runHook preBuild
 
     HOME=$TMPDIR
+
     emmake make
 
     runHook postBuild