diff -Nru marble-15.12.3/debian/changelog marble-15.12.3/debian/changelog
--- marble-15.12.3/debian/changelog	2016-04-14 23:24:24.000000000 +0000
+++ marble-15.12.3/debian/changelog	2016-04-15 14:10:59.000000000 +0000
@@ -1,3 +1,11 @@
+marble (4:15.12.3-0ubuntu2) xenial; urgency=medium
+
+  * Add uptream patch to fix isnan with new libc6.
+  * Release to archive. 
+  * Add patch.
+
+ -- Scarlett Clark <sgclark@kubuntu.org>  Fri, 15 Apr 2016 07:09:11 -0700
+
 marble (4:15.12.3-0ubuntu1) xenial; urgency=medium
 
   * New upstream bugfix release. 
diff -Nru marble-15.12.3/debian/patches/series marble-15.12.3/debian/patches/series
--- marble-15.12.3/debian/patches/series	2016-04-14 23:24:24.000000000 +0000
+++ marble-15.12.3/debian/patches/series	2016-04-15 14:10:59.000000000 +0000
@@ -1,2 +1,3 @@
 do_not_install_private_headers
 kubuntu_disable-MarbleRunnerManagerTest.diff
+upstream_fix_isnan_libc6.patch
\ No newline at end of file
diff -Nru marble-15.12.3/debian/patches/upstream_fix_isnan_libc6.patch marble-15.12.3/debian/patches/upstream_fix_isnan_libc6.patch
--- marble-15.12.3/debian/patches/upstream_fix_isnan_libc6.patch	1970-01-01 00:00:00.000000000 +0000
+++ marble-15.12.3/debian/patches/upstream_fix_isnan_libc6.patch	2016-04-15 14:10:59.000000000 +0000
@@ -0,0 +1,67 @@
+From 486f6181d6fef15c9b6c72504e3588be502bea80 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Dennis=20Nienh=C3=BCser?= <nienhueser@kde.org>
+Date: Sun, 20 Mar 2016 17:43:25 +0100
+Subject: [PATCH] Use std::isnan from cmath
+
+---
+ .../positionprovider/gpsd/GpsdPositionProviderPlugin.cpp | 16 ++++++++--------
+ 1 file changed, 8 insertions(+), 8 deletions(-)
+
+diff --git a/src/plugins/positionprovider/gpsd/GpsdPositionProviderPlugin.cpp b/src/plugins/positionprovider/gpsd/GpsdPositionProviderPlugin.cpp
+index 20ec8c6..946cdc4 100644
+--- a/src/plugins/positionprovider/gpsd/GpsdPositionProviderPlugin.cpp
++++ b/src/plugins/positionprovider/gpsd/GpsdPositionProviderPlugin.cpp
+@@ -12,7 +12,7 @@
+ 
+ #include "GpsdThread.h"
+ #include "MarbleDebug.h"
+-#include <math.h>
++#include <cmath>
+ 
+ using namespace Marble;
+ /* TRANSLATOR Marble::GpsdPositionProviderPlugin */
+@@ -76,7 +76,7 @@ void GpsdPositionProviderPlugin::update( gps_data_t data )
+ {
+     PositionProviderStatus oldStatus = m_status;
+     GeoDataCoordinates oldPosition = m_position;
+-    if ( data.status == STATUS_NO_FIX || isnan( data.fix.longitude ) || isnan( data.fix.latitude ) )
++    if ( data.status == STATUS_NO_FIX || std::isnan( data.fix.longitude ) || std::isnan( data.fix.latitude ) )
+         m_status = PositionProviderStatusAcquiring;
+     else {
+         m_status = PositionProviderStatusAvailable;
+@@ -88,29 +88,29 @@ void GpsdPositionProviderPlugin::update( gps_data_t data )
+ 
+         m_accuracy.level = GeoDataAccuracy::Detailed;
+ #if defined( GPSD_API_MAJOR_VERSION ) && ( GPSD_API_MAJOR_VERSION >= 3 )
+-        if ( !isnan( data.fix.epx ) && !isnan( data.fix.epy ) ) {
++        if ( !std::isnan( data.fix.epx ) && !std::isnan( data.fix.epy ) ) {
+             m_accuracy.horizontal = qMax( data.fix.epx, data.fix.epy );
+         }
+ #else
+-        if ( !isnan( data.fix.eph ) ) {
++        if ( !std::isnan( data.fix.eph ) ) {
+             m_accuracy.horizontal = data.fix.eph;
+         }
+ #endif
+-        if ( !isnan( data.fix.epv ) ) {
++        if ( !std::isnan( data.fix.epv ) ) {
+             m_accuracy.vertical = data.fix.epv;
+         }
+ 
+-        if( !isnan(data.fix.speed ) )
++        if( !std::isnan(data.fix.speed ) )
+         {
+             m_speed = data.fix.speed;
+         }
+ 
+-        if( !isnan( data.fix.track ) )
++        if( !std::isnan( data.fix.track ) )
+         {
+             m_track = data.fix.track;
+         }
+ 
+-        if ( !isnan( data.fix.time ) )
++        if ( !std::isnan( data.fix.time ) )
+         {
+             m_timestamp = QDateTime::fromMSecsSinceEpoch( data.fix.time * 1000 );
+         }