From 8974ba2d2fd6ff6a0739102b4c698665be836718 Mon Sep 17 00:00:00 2001
From: Mark Liversedge <liversedge@gmail.com>
Date: Sun, 26 Jan 2014 16:22:00 +0000
Subject: [PATCH] Fix WPrime CP lookup SEGV

.. when zones or cp not set for the date in question

Fixes #774.
---
 src/WPrime.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/WPrime.cpp b/src/WPrime.cpp
index 44f177a05..f22f2d63c 100644
--- a/src/WPrime.cpp
+++ b/src/WPrime.cpp
@@ -535,8 +535,8 @@ class WPrimeExp : public RideMetric {
                  const Context *) {
 
         int cp = r->getTag("CP","0").toInt();
-        if (!cp) cp = zones->getCP(zonerange);
-    
+        if (!cp && zones && zonerange >=0) cp = zones->getCP(zonerange);
+
         double total = 0;
         double secs = 0;
         foreach(const RideFilePoint *point, r->dataPoints()) {