diff --git a/gtk2_ardour/editor.cc b/gtk2_ardour/editor.cc
index d97867bb69..b841efb542 100644
--- a/gtk2_ardour/editor.cc
+++ b/gtk2_ardour/editor.cc
@@ -2278,7 +2278,7 @@ Editor::set_edit_point_preference (EditPoint ep, bool force)
 		break;
 	}
 
-	const char* action;
+	const char* action=NULL;
 
 	switch (_edit_point) {
 	case EditAtPlayhead:
@@ -4382,7 +4382,7 @@ Editor::idle_visual_changer ()
 
 	if (p & VisualChange::TimeOrigin) {
 
-		nframes64_t csf, cef;
+		nframes64_t csf=0, cef=0;
 		nframes64_t current_time_origin = (nframes64_t) floor (horizontal_adjustment.get_value() * frames_per_unit);
 
 		if (session) {
diff --git a/gtk2_ardour/editor_mouse.cc b/gtk2_ardour/editor_mouse.cc
index 6cef53a685..ab1f4792eb 100644
--- a/gtk2_ardour/editor_mouse.cc
+++ b/gtk2_ardour/editor_mouse.cc
@@ -2344,7 +2344,7 @@ Editor::start_marker_grab (ArdourCanvas::Item* item, GdkEvent* event)
 void
 Editor::marker_drag_motion_callback (ArdourCanvas::Item* item, GdkEvent* event)
 {
-	nframes64_t f_delta;	
+	nframes64_t f_delta = 0;
 	nframes64_t newframe;
 	bool is_start;
 	bool move_both = false;
diff --git a/gtk2_ardour/editor_ops.cc b/gtk2_ardour/editor_ops.cc
index e3d2f88a20..139e07a366 100644
--- a/gtk2_ardour/editor_ops.cc
+++ b/gtk2_ardour/editor_ops.cc
@@ -3257,9 +3257,9 @@ Editor::align_selection_relative (RegionPoint point, nframes64_t position, const
 		return;
 	}
 
-	nframes64_t distance;
+	nframes64_t distance = 0;
 	nframes64_t pos = 0;
-	int dir;
+	int dir = 1;
 
 	list<RegionView*> sorted;
 	rs.by_position (sorted);
@@ -3271,7 +3271,6 @@ Editor::align_selection_relative (RegionPoint point, nframes64_t position, const
 		pos = position;
 		if (position > r->position()) {
 			distance = position - r->position();
-			dir = 1;
 		} else {
 			distance = r->position() - position;
 			dir = -1;
@@ -3282,7 +3281,6 @@ Editor::align_selection_relative (RegionPoint point, nframes64_t position, const
 		if (position > r->last_frame()) {
 			distance = position - r->last_frame();
 			pos = r->position() + distance;
-			dir = 1;
 		} else {
 			distance = r->last_frame() - position;
 			pos = r->position() - distance;
@@ -3294,7 +3292,6 @@ Editor::align_selection_relative (RegionPoint point, nframes64_t position, const
 		pos = r->adjust_to_sync (position);
 		if (pos > r->position()) {
 			distance = pos - r->position();
-			dir = 1;
 		} else {
 			distance = r->position() - pos;
 			dir = -1;
@@ -4740,7 +4737,7 @@ Editor::toggle_fade_active (bool in)
 
 	const char* cmd = (in ? _("toggle fade in active") : _("toggle fade out active"));
 	bool have_switch = false;
-	bool yn;
+	bool yn = false;
 
 	begin_reversible_command (cmd);
 
diff --git a/libs/ardour/crossfade.cc b/libs/ardour/crossfade.cc
index f2641a43e2..e73d79a553 100644
--- a/libs/ardour/crossfade.cc
+++ b/libs/ardour/crossfade.cc
@@ -821,7 +821,7 @@ Crossfade::set_follow_overlap (bool yn)
 nframes_t
 Crossfade::set_length (nframes_t len)
 {
-	nframes_t limit;
+	nframes_t limit = 0;
 
 	switch (_anchor_point) {
 	case StartOfIn:
diff --git a/libs/ardour/insert.cc b/libs/ardour/insert.cc
index 35b820dad3..0227da8246 100644
--- a/libs/ardour/insert.cc
+++ b/libs/ardour/insert.cc
@@ -430,11 +430,9 @@ PluginInsert::automation_run (vector<Sample *>& bufs, uint32_t nbufs, nframes_t
  	}
 
 	nframes_t buffer_correct = 0;
-	int i;
-
 	
  	while (nframes) {
-                nframes_t cnt = min (((nframes_t) ceil (next_event.when) - now), nframes);
+		nframes_t cnt = min (((nframes_t) ceil (next_event.when) - now), nframes);
 
 		// This is called first, but nframes = 256
  		connect_and_run (bufs, nbufs, cnt, offset, true, now);
@@ -444,7 +442,7 @@ PluginInsert::automation_run (vector<Sample *>& bufs, uint32_t nbufs, nframes_t
 		now += cnt;
 		buffer_correct += cnt;
 
-		for (i = 0; i < nbufs; i++) {
+		for (uint32_t i = 0; i < nbufs; i++) {
 			bufs[i] += cnt;
 		}
 
@@ -459,7 +457,7 @@ PluginInsert::automation_run (vector<Sample *>& bufs, uint32_t nbufs, nframes_t
  		connect_and_run (bufs, nbufs, nframes, offset, true, now);
   	}
 
-	for (i = 0; i < nbufs; i++) {
+	for (uint32_t i = 0; i < nbufs; i++) {
 		bufs[i] -= buffer_correct;
 	}
 }	
diff --git a/libs/ardour/resampled_source.cc b/libs/ardour/resampled_source.cc
index 7db917635c..fec2a3f624 100644
--- a/libs/ardour/resampled_source.cc
+++ b/libs/ardour/resampled_source.cc
@@ -37,7 +37,7 @@ ResampledImportableSource::ResampledImportableSource (boost::shared_ptr<Importab
 	
 	/* Initialize the sample rate converter. */
 	
-	int src_type;
+	int src_type = SRC_SINC_BEST_QUALITY;
 
 	switch (srcq) {
 	case SrcBest:
diff --git a/libs/ardour/sndfilesource.cc b/libs/ardour/sndfilesource.cc
index e24acc38fa..d2b4704daf 100644
--- a/libs/ardour/sndfilesource.cc
+++ b/libs/ardour/sndfilesource.cc
@@ -50,7 +50,7 @@ const AudioFileSource::Flag SndFileSource::default_writable_flags = AudioFileSou
 											   AudioFileSource::CanRename);
 
 static void
-snprintf_bounded_null_filled (char* target, size_t target_size, char* fmt, ...)
+snprintf_bounded_null_filled (char* target, size_t target_size, const char* fmt, ...)
 {
 	char buf[target_size+1];
 	va_list ap;