From db7beefbe49d2ec6fa24ac98a2dad08eaf8f28e1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Motiejus=20Jak=C5=A1tys?= <motiejus@jakstys.lt>
Date: Fri, 12 Aug 2022 09:25:37 +0300
Subject: [PATCH] c++: fall back to cache dir in /tmp

rules_go is making calls that do `env - <...>` and are setting neither
TMPDIR nor HOME. So we should always fallback somewhere.
---
 toolchain/defs.bzl | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/toolchain/defs.bzl b/toolchain/defs.bzl
index 73f8fda..965cf22 100644
--- a/toolchain/defs.bzl
+++ b/toolchain/defs.bzl
@@ -80,12 +80,15 @@ ZIG_TOOL_WRAPPER = """#!/usr/bin/env bash
 set -e
 
 if [[ -n "$TMPDIR" ]]; then
-  _cache_prefix=$TMPDIR
+    _cache_prefix=$TMPDIR
+elif [[ -n "$HOME" ]]; then
+    if [[ "$(uname)" = Darwin ]]; then
+        _cache_prefix="$HOME/Library/Caches"
+    else
+        _cache_prefix="$HOME/.cache"
+    fi
 else
-  _cache_prefix="$HOME/.cache"
-  if [[ "$(uname)" = Darwin ]]; then
-    _cache_prefix="$HOME/Library/Caches"
-  fi
+    _cache_prefix=/tmp
 fi
 
 export ZIG_LOCAL_CACHE_DIR="$_cache_prefix/bazel-zig-cc"