From b564fa2e71ab623ccffd16fd0b5cecb80c978aa9 Mon Sep 17 00:00:00 2001
From: Emin <me@emin.chat>
Date: Fri, 14 Aug 2026 16:04:00 +0800
Subject: [PATCH] liberty_cache: key SCL cache on ABC executable mtime and size

The SCL format is written/read by ABC and can change between ABC builds,
so a cache entry created with a different ABC binary must not be reused.
---
 passes/techmap/liberty_cache.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/passes/techmap/liberty_cache.h b/passes/techmap/liberty_cache.h
index baab8f8be..9cb8752f1 100644
--- a/passes/techmap/liberty_cache.h
+++ b/passes/techmap/liberty_cache.h
@@ -37,6 +37,14 @@ inline std::string convert_liberty_files_to_merged_scl(const std::vector<std::st
 	std::string hash_input;
 	time_t newest_mtime = 0;
 
+	// The SCL format is written/read by ABC and can change between ABC builds,
+	// so the cache key must identify the ABC executable.
+	if (!abc_exe.empty()) {
+		struct stat abc_stat;
+		if (stat(abc_exe.c_str(), &abc_stat) == 0)
+			hash_input += stringf("|abc:%s:%lld:%lld", abc_exe.c_str(), (long long)abc_stat.st_mtime, (long long)abc_stat.st_size);
+	}
+
 	for (const std::string &liberty_file : sorted_files) {
 		struct stat liberty_stat;
 		if (stat(liberty_file.c_str(), &liberty_stat) != 0) {