From 9c33cc2c6bdc1765588b610aae1c6f2d6dce4ea6 Mon Sep 17 00:00:00 2001
From: Alexander Grund <alexander.grund@tu-dresden.de>
Date: Wed, 27 Nov 2024 10:28:17 +0100
Subject: [PATCH] Avoid caching build artefacts

When we copy the whole boost-root AFTER the build(s) it will contain
also build artefacts such as the bin.v2 folder.
When restoring that later B2 might skip parts of the build although it
should not.
Make a copy after the initial setup & bootstrap.
---
 .github/workflows/ci.yml | 4 ++--
 ci/github/install.sh     | 5 +++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a33de29a..5cefb72f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -280,8 +280,8 @@ jobs:
           COVERITY_SCAN_TOKEN: ${{ secrets.COVERITY_SCAN_TOKEN }}
 
       - name: Prepare for cache
-        if: ${{ env.BOOST_ROOT != '' }}
-        run: rm -rf boost-root; mv "${BOOST_ROOT}" boost-root
+        if: ${{ env.BOOST_ROOT_CACHE != '' }}
+        run: rm -rf boost-root; mv "${BOOST_ROOT_CACHE}" boost-root
         working-directory: ${{github.workspace}}
   windows:
     defaults:
diff --git a/ci/github/install.sh b/ci/github/install.sh
index c45cc798..60049679 100644
--- a/ci/github/install.sh
+++ b/ci/github/install.sh
@@ -33,6 +33,11 @@ fi
 
 . $(dirname "${BASH_SOURCE[0]}")/../common_install.sh
 
+# Save the state before building anything to avoid caching build artefacts
+BOOST_ROOT_CACHE="${BOOST_ROOT}-for-cache"
+echo "BOOST_ROOT_CACHE=$BOOST_ROOT_CACHE" >> $GITHUB_ENV
+cp -r "$BOOST_ROOT" "$BOOST_ROOT_CACHE"
+
 # Persist the environment for all future steps
 
 # Set by common_install.sh