1 files changed, 32 insertions, 0 deletions
diff --git a/src/ci/scripts/install-msys2.sh b/src/ci/scripts/install-msys2.sh
new file mode 100755
index 000000000..0aa4b42a6
--- /dev/null
+++ b/src/ci/scripts/install-msys2.sh
@@ -0,0 +1,32 @@
+#!/bin/bash
+# Download and install MSYS2, needed primarily for the test suite (run-make) but
+# also used by the MinGW toolchain for assembling things.
+
+set -euo pipefail
+IFS=$'\n\t'
+
+source "$(cd "$(dirname "$0")" && pwd)/../shared.sh"
+
+if isWindows; then
+    msys2Path="c:/msys64"
+    mkdir -p "${msys2Path}/home/${USERNAME}"
+    ciCommandAddPath "${msys2Path}/usr/bin"
+
+    # Detect the native Python version installed on the agent. On GitHub
+    # Actions, the C:\hostedtoolcache\windows\Python directory contains a
+    # subdirectory for each installed Python version.
+    #
+    # The -V flag of the sort command sorts the input by version number.
+    native_python_version="$(ls /c/hostedtoolcache/windows/Python | sort -Vr | head -n 1)"
+
+    # Make sure we use the native python interpreter instead of some msys equivalent
+    # one way or another. The msys interpreters seem to have weird path conversions
+    # baked in which break LLVM's build system one way or another, so let's use the
+    # native version which keeps everything as native as possible.
+    python_home="/c/hostedtoolcache/windows/Python/${native_python_version}/x64"
+    if ! [[ -f "${python_home}/python3.exe" ]]; then
+        cp "${python_home}/python.exe" "${python_home}/python3.exe"
+    fi
+    ciCommandAddPath "C:\\hostedtoolcache\\windows\\Python\\${native_python_version}\\x64"
+    ciCommandAddPath "C:\\hostedtoolcache\\windows\\Python\\${native_python_version}\\x64\\Scripts"
+fi