From fbaca1ed7ece82dbbf4e5a0f444f0151746f0604 Mon Sep 17 00:00:00 2001
From: "Rune K. Svendsen" <runesvend@gmail.com>
Date: Mon, 13 Jan 2025 08:04:53 +0100
Subject: [PATCH] CI: don't share cache between C compilers

The "Cache cabal files"-step would restore a cache from a key that does not include the C compiler, which means e.g. Clang could restore stuff built by GCC.

Also, the `restore-keys` key didn't even include the GHC version. This meant that -- in case of a cache miss for `key` -- a cache built by one GHC version could be pulled for a CI run for another GHC version.
---
 .github/workflows/cabal-in-nix-shell.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/cabal-in-nix-shell.yml b/.github/workflows/cabal-in-nix-shell.yml
index 18c4829..8c7a75f 100644
--- a/.github/workflows/cabal-in-nix-shell.yml
+++ b/.github/workflows/cabal-in-nix-shell.yml
@@ -42,8 +42,8 @@ jobs:
             ~/.cabal/packages
             ~/.cabal/store
             dist-newstyle
-          key: ${{ runner.os }}-${{ matrix.os }}-${{ hashFiles('**/*.cabal', '**/cabal.project', '**/cabal.project.freeze') }}--${{ matrix.ghc }}
-          restore-keys: ${{ runner.os }}-${{ matrix.os }}-
+          key: ${{ runner.os }}-${{ matrix.os }}-${{ matrix.ghc }}-${{ matrix.cc }}-${{ hashFiles('**/*.cabal', '**/cabal.project', '**/cabal.project.freeze') }}
+          restore-keys: ${{ runner.os }}-${{ matrix.os }}-${{ matrix.ghc }}-${{ matrix.cc }}-
 
       # Make nix-shell use specific Bash version.
       # Cf. https://nixos.org/manual/nix/stable/command-ref/nix-shell#environment-variables.