1 files changed, 33 insertions, 0 deletions
diff --git a/build-aux/gcov-prune b/build-aux/gcov-prune
new file mode 100755
index 0000000..dc190a9
--- /dev/null
+++ b/build-aux/gcov-prune
@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+# build-aux/gcov-prune - Prune old GCC coverage files
+#
+# Copyright (C) 2025  Luke T. Shumaker <lukeshu@lukeshu.com>
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+set -e
+
+[[ $# == 1 ]]
+
+sourcedir="$(realpath -- .)"
+builddir="$(realpath -- "$1")"
+
+# `gcc` writes .gcno
+# Running the program writes .gcda (updates existing files, concurrent-safe)
+# GCC `gcov` post-processes .gcno+.gcda to .gcov
+# `gcovr` is a Python script that calls `gcov` and merges and post-processes the .gcov files to other formats
+
+# Prune orphaned .gcno files.
+find "$builddir" -name '*.gcno' -printf '%P\0' | while read -d '' -r gcno_file; do
+	rel_base="${gcno_file%/CMakeFiles/*}"
+	src_file="$gcno_file"
+	src_file="${src_file#*/CMakeFiles/*.dir/}"
+	src_file="${src_file%.gcno}"
+	src_file="${src_file//__/..}"
+	src_file="$rel_base/$src_file"
+	if [[ ! -e "$sourcedir/$src_file" || "$sourcedir/$src_file" -nt "$builddir/$gcno_file" ]]; then
+		rm -fv -- "$builddir/$gcno_file"
+	fi
+done
+
+# Prune all .gcda files.
+find "$builddir" -name '*.gcda' -delete