diff --git a/common/log.c b/common/log.c
index 23b756eb..8e5b71f9 100644
--- a/common/log.c
+++ b/common/log.c
@@ -142,14 +142,14 @@ void sway_log_errno(log_importance_t verbosity, char* format, ...) {
 	}
 }
 
-bool _sway_assert(bool condition, const char* format, ...) {
+bool _sway_assert(bool condition, const char *filename, int line, const char* format, ...) {
 	if (condition) {
 		return true;
 	}
 
 	va_list args;
 	va_start(args, format);
-	sway_vlog(L_ERROR, format, args);
+	_sway_vlog(filename, line, L_ERROR, format, args);
 	va_end(args);
 
 #ifndef NDEBUG
diff --git a/include/log.h b/include/log.h
index 60b3763b..32981b62 100644
--- a/include/log.h
+++ b/include/log.h
@@ -19,9 +19,9 @@ void sway_log_colors(int mode);
 void sway_log_errno(log_importance_t verbosity, char* format, ...) __attribute__((format(printf,2,3)));
 void sway_abort(const char* format, ...) __attribute__((format(printf,1,2)));
 
-bool _sway_assert(bool condition, const char* format, ...) __attribute__((format(printf,2,3)));
+bool _sway_assert(bool condition, const char *filename, int line, const char* format, ...) __attribute__((format(printf,4,5)));
 #define sway_assert(COND, FMT, ...) \
-	_sway_assert(COND, "%s:" FMT, __PRETTY_FUNCTION__, ##__VA_ARGS__)
+	_sway_assert(COND, __FILE__, __LINE__, "%s:" FMT, __PRETTY_FUNCTION__, ##__VA_ARGS__)
 
 void _sway_log(const char *filename, int line, log_importance_t verbosity, const char* format, ...) __attribute__((format(printf,4,5)));