diff --git a/CI/ci-linux-prepare.sh b/CI/ci-linux-prepare.sh
index a73ff7d0..0ce3ff3b 100755
--- a/CI/ci-linux-prepare.sh
+++ b/CI/ci-linux-prepare.sh
@@ -8,7 +8,7 @@ MAKE_OPTIONS=""
 BUILDPATH=""
 
 # set GTEST path
-OPTIONS="-DGTEST_ROOT=/usr/src/gtest/"
+OPTIONS="-DGTEST_ROOT=~/sw/gtest-1.10.0"
 
 if [ "$COMPILER" == "gcc" ]; then
   echo "Building with GCC";
diff --git a/src/OpenMesh/Core/IO/reader/PLYReader.cc b/src/OpenMesh/Core/IO/reader/PLYReader.cc
index db431c14..84d9fd78 100644
--- a/src/OpenMesh/Core/IO/reader/PLYReader.cc
+++ b/src/OpenMesh/Core/IO/reader/PLYReader.cc
@@ -54,6 +54,7 @@
 #include <fstream>
 #include <iostream>
 #include <memory>
+#include <string>
 
 #ifndef WIN32
 #endif
@@ -1089,7 +1090,7 @@ std::string get_property_name(std::string _string1, std::string _string2) {
 
 //-----------------------------------------------------------------------------
 
-_PLYReader_::ValueType get_property_type(std::string& _string1, std::string& _string2) {
+_PLYReader_::ValueType get_property_type(const std::string& _string1, const std::string& _string2) {
 
     if (_string1 == "float32" || _string2 == "float32")
 
diff --git a/src/OpenMesh/Tools/VDPM/VHierarchyNodeIndex.hh b/src/OpenMesh/Tools/VDPM/VHierarchyNodeIndex.hh
index 928b14fe..70fc7fdf 100644
--- a/src/OpenMesh/Tools/VDPM/VHierarchyNodeIndex.hh
+++ b/src/OpenMesh/Tools/VDPM/VHierarchyNodeIndex.hh
@@ -87,9 +87,6 @@ public:
   explicit VHierarchyNodeIndex(unsigned int _value)
   { value_ = _value; }
 
-  VHierarchyNodeIndex(const VHierarchyNodeIndex &_other)
-  { value_ = _other.value_; }
-
   VHierarchyNodeIndex(unsigned int   _tree_id, 
 		      unsigned int   _node_id, 
 		      unsigned short _tree_id_bits)