disallow tempi of 0 ntpm or less.

diff --git a/libs/ardour/tempo.cc b/libs/ardour/tempo.cc
index 7c281a3e13143216888afa93507ec4db5c557640..7bb542fb510beaa179ba29d71f54a6ec32ea0f08 100644 (file)
--- a/libs/ardour/tempo.cc
+++ b/libs/ardour/tempo.cc
@@ -1058,6 +1058,10 @@ TempoMap::do_insert (MetricSection* section)
 TempoSection*
 TempoMap::add_tempo (const Tempo& tempo, const double& pulse, const framepos_t& frame, ARDOUR::TempoSection::Type type, PositionLockStyle pls)
 {
+       if (tempo.note_types_per_minute() <= 0.0) {
+               return 0;
+       }
+
        TempoSection* ts = 0;
        {
                Glib::Threads::RWLock::WriterLock lm (lock);
@@ -1073,6 +1077,10 @@ TempoMap::add_tempo (const Tempo& tempo, const double& pulse, const framepos_t&
 void
 TempoMap::replace_tempo (const TempoSection& ts, const Tempo& tempo, const double& pulse, const framepos_t& frame, TempoSection::Type type, PositionLockStyle pls)
 {
+       if (tempo.note_types_per_minute() <= 0.0) {
+               return;
+       }
+
        const bool locked_to_meter = ts.locked_to_meter();
 
        {