From 630a87d9a976446201bf3f101d714e85d2bcd19a Mon Sep 17 00:00:00 2001
From: Jonathan Challinger <mr.challinger@gmail.com>
Date: Mon, 12 May 2014 14:55:37 -0700
Subject: [PATCH] AP_Buffer: remove scalar assignment so that non-scalars can
 be buffered

---
 libraries/AP_Buffer/AP_Buffer.h | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/libraries/AP_Buffer/AP_Buffer.h b/libraries/AP_Buffer/AP_Buffer.h
index 1cc52cc0ff..f8b8c1149c 100644
--- a/libraries/AP_Buffer/AP_Buffer.h
+++ b/libraries/AP_Buffer/AP_Buffer.h
@@ -107,14 +107,16 @@ T AP_Buffer<T,SIZE>::pop_front()
 {
 	T result;
 
-	// return zero if buffer is empty
-	if( _num_items == 0 ) {
-		return 0;
-	}
-
 	// get next value in buffer
     result = _buff[_head];
 
+    if(_num_items == 0) {
+        // return whatever is at _head
+        // don't return zero because it is a scalar value
+        // don't return T() because PX4 compiler does not support it
+        return result;
+    }
+
     // increment to next point
     _head++;
     if( _head >= SIZE )
@@ -132,12 +134,6 @@ const T& AP_Buffer<T,SIZE>::peek(uint8_t position) const
 {
     uint8_t j = _head + position;
 
-    // return zero if position is out of range
-    if( position >= _num_items ) {
-    	const static T r = 0;
-        return r;
-    }
-
     // wrap around if necessary
     if( j >= SIZE )
         j -= SIZE;