From 30b6ae90f35aed3c93ef01860c049c1421b38145 Mon Sep 17 00:00:00 2001
From: LM <lm@student.ethz.ch>
Date: Mon, 14 Nov 2011 08:39:45 +0100
Subject: [PATCH] Added UAVObject sorting to make UAVObj structs align to
 word-boundaries. Else copying to / from UAVObjects will fail on Cortex M4
 with an alignment error, since the proper alignment is not visible to the
 compiler in a line like this: float* data = UAVObj.Roll; data[2] = yaw;

---
 .gitignore                                 | 2 ++
 ground/uavobjgenerator/uavobjectparser.cpp | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/.gitignore b/.gitignore
index 6c4d8b39f..03797f84f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,5 @@
+# Exclude temporary and system files
+.DS_Store
 
 # /flight/
 /flight/*.pnproj
diff --git a/ground/uavobjgenerator/uavobjectparser.cpp b/ground/uavobjgenerator/uavobjectparser.cpp
index cba02f8ee..414712658 100644
--- a/ground/uavobjgenerator/uavobjectparser.cpp
+++ b/ground/uavobjgenerator/uavobjectparser.cpp
@@ -111,6 +111,11 @@ int UAVObjectParser::getNumBytes(int objIndex)
     }
 }
 
+bool fieldTypeLessThan(const FieldInfo* f1, const FieldInfo* f2)
+{
+    return f1->numBytes > f2->numBytes;
+}
+
 /**
  * Parse supplied XML file
  * @param xml The xml text
@@ -200,6 +205,9 @@ QString UAVObjectParser::parseXML(QString& xml, QString& filename)
             // Get next element
             childNode = childNode.nextSibling();
         }
+		
+		// Sort all fields according to size
+        qStableSort(info->fields.begin(), info->fields.end(), fieldTypeLessThan);
 
         // Make sure that required elements were found
         if ( !accessFound )