Limited old cached objects detection

libevmjit/Cache.cpp

@@ -36,6 +36,20 @@ std::unique_ptr<llvm::Module> Cache::getObject(std::string const& id)
 	llvm::sys::path::system_temp_directory(false, cachePath);
 	llvm::sys::path::append(cachePath, "evm_objs", id);
 
+#if defined(__GNUC__) && !defined(NDEBUG)
+	llvm::sys::fs::file_status st;
+	auto err = llvm::sys::fs::status(cachePath.str(), st);
+	if (err)
+		return nullptr;
+	auto mtime = st.getLastModificationTime().toEpochTime();
+
+	std::tm tm;
+	strptime(__DATE__ __TIME__, " %b %d %Y %H:%M:%S", &tm);
+	auto btime = (uint64_t)std::mktime(&tm);
+	if (btime > mtime)
+		return nullptr;
+#endif
+
 	if (auto r = llvm::MemoryBuffer::getFile(cachePath.str(), -1, false))
 		lastObject = llvm::MemoryBuffer::getMemBufferCopy(r.get()->getBuffer());
 	else if (r.getError() != std::make_error_code(std::errc::no_such_file_or_directory))