diff --git a/kernel/driver.cc b/kernel/driver.cc
index 2917586ea..74f53901e 100644
--- a/kernel/driver.cc
+++ b/kernel/driver.cc
@@ -558,6 +558,9 @@ int main(int argc, char **argv)
 		fprintf(f, "\n");
 	}
 
+	if (log_expect_no_warnings && log_warnings_count)
+		log_error("Warnings: %d unique messages, %d total\n", GetSize(log_warnings), log_warnings_count);
+
 	if (print_stats)
 	{
 		std::string hash = log_hasher->final().substr(0, 10);
diff --git a/kernel/log.cc b/kernel/log.cc
index 89a403e63..1575b4fed 100644
--- a/kernel/log.cc
+++ b/kernel/log.cc
@@ -45,6 +45,7 @@ std::vector<std::regex> log_warn_regexes, log_nowarn_regexes, log_werror_regexes
 std::vector<std::pair<std::regex,LogExpectedItem>> log_expect_log, log_expect_warning, log_expect_error;
 std::set<std::string> log_warnings, log_experimentals, log_experimentals_ignored;
 int log_warnings_count = 0;
+bool log_expect_no_warnings = false;
 bool log_hdump_all = false;
 FILE *log_errfile = NULL;
 SHA1 *log_hasher = NULL;
diff --git a/kernel/log.h b/kernel/log.h
index 0f912fccb..79de1a20a 100644
--- a/kernel/log.h
+++ b/kernel/log.h
@@ -52,6 +52,7 @@ extern std::map<std::string, std::set<std::string>> log_hdump;
 extern std::vector<std::regex> log_warn_regexes, log_nowarn_regexes, log_werror_regexes;
 extern std::set<std::string> log_warnings, log_experimentals, log_experimentals_ignored;
 extern int log_warnings_count;
+extern bool log_expect_no_warnings;
 extern bool log_hdump_all;
 extern FILE *log_errfile;
 extern SHA1 *log_hasher;
diff --git a/passes/cmds/logger.cc b/passes/cmds/logger.cc
index 30768980e..947b178c5 100644
--- a/passes/cmds/logger.cc
+++ b/passes/cmds/logger.cc
@@ -60,6 +60,9 @@ struct LoggerPass : public Pass {
 		log("    -expect <type> <regex> <expected_count>\n");
 		log("        expect log,warning or error to appear. In case of error return code is 0.\n");
 		log("\n");
+		log("    -expect-no-warnings\n");
+		log("        gives error in case there is at least one warning.\n");
+		log("\n");
 	}
 
 	void execute(std::vector<std::string> args, RTLIL::Design * design) YS_OVERRIDE
@@ -166,6 +169,10 @@ struct LoggerPass : public Pass {
 
 				continue;
 			}
+			if (args[argidx] == "-expect-no-warnings") {
+				log_expect_no_warnings = true;
+				continue;
+			}
 			break;
 		}
 		extra_args(args, argidx, design, false);