From 8440ec08d0610910f4773b643e2fc6541b7f5470 Mon Sep 17 00:00:00 2001
From: figsoda <figsoda@pm.me>
Date: Thu, 30 Mar 2023 19:23:28 -0400
Subject: [PATCH] ruff: fix on emulated x86_64-darwin

---
 pkgs/development/tools/ruff/default.nix | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/pkgs/development/tools/ruff/default.nix b/pkgs/development/tools/ruff/default.nix
index e732e6f24c80..78bf24389070 100644
--- a/pkgs/development/tools/ruff/default.nix
+++ b/pkgs/development/tools/ruff/default.nix
@@ -40,6 +40,12 @@ rustPlatform.buildRustPackage rec {
   cargoBuildFlags = [ "--package=ruff_cli" ];
   cargoTestFlags = cargoBuildFlags;
 
+  preBuild = lib.optionalString (stdenv.isDarwin && stdenv.isx86_64) ''
+    # See https://github.com/jemalloc/jemalloc/issues/1997
+    # Using a value of 48 should work on both emulated and native x86_64-darwin.
+    export JEMALLOC_SYS_WITH_LG_VADDR=48
+  '';
+
   postInstall = ''
     installShellCompletion --cmd ruff \
       --bash <($out/bin/ruff generate-shell-completion bash) \