diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8fc19fe0..9660f557 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -27,31 +27,32 @@ ELSE()
 ENDIF()
 
 IF(MSVC)
-  add_compile_options(/wd4514 /wd4267 $<$<CONFIG:DEBUG>:/bigobj>)
+  add_compile_options(/wd4514 /wd4267 /bigobj)
+  add_definitions(-D_USE_MATH_DEFINES)
 ELSE()
   IF (CMAKE_SYSTEM_PROCESSOR MATCHES "(arm64)|(ARM64)|(aarch64)|(AARCH64)")
-    add_definitions (-Wall -march=armv8-a -O3)
+    add_definitions (-march=armv8-a)
   ELSEIF (CMAKE_SYSTEM_PROCESSOR MATCHES 
           "(arm)|(ARM)|(armhf)|(ARMHF)|(armel)|(ARMEL)")
-    add_definitions (-Wall -march=armv7-a -O3)
+    add_definitions (-march=armv7-a)
   ELSE ()
-    add_definitions (-Wall -march=native -O3) #TODO use correct c++11 def once everybody has moved to gcc 4.7 # for now I even removed std=gnu++0x
+    add_definitions (-march=native) #TODO use correct c++11 def once everybody has moved to gcc 4.7 # for now I even removed std=gnu++0x
   ENDIF()
+  add_definitions (
+    -O3
+    -Wall
+    -Wextra
+    #-Werror
+    -Wwrite-strings
+    -Wno-unused-parameter
+    -fno-strict-aliasing
+  )
 ENDIF()
 
 IF(BUILD_POSITION_INDEPENDENT_CODE)
   add_definitions( -fPIC )
 ENDIF()
 
-ADD_DEFINITIONS (
--Wall
--Wextra
-#-Werror
--Wwrite-strings
--Wno-unused-parameter
--fno-strict-aliasing
-)
-
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${PROJECT_SOURCE_DIR}/modules/")
 find_package(Eigen REQUIRED)
 set(ADDITIONAL_INCLUDE_DIRS ${EIGEN_INCLUDE_DIRS} ${EIGEN_INCLUDE_DIR}/unsupported)
diff --git a/src/absolute_pose/modules/main.cpp b/src/absolute_pose/modules/main.cpp
index 7cff9f69..ed0c271a 100644
--- a/src/absolute_pose/modules/main.cpp
+++ b/src/absolute_pose/modules/main.cpp
@@ -770,7 +770,7 @@ opengv::absolute_pose::modules::upnp_main(
     {
       Eigen::Matrix<double,10,1> s;
       upnp_fill_s(quaternion,s);
-      Eigen::Matrix<double,1,1> valueM = s.transpose() * M * s + 2.0 * C * s;
+      Eigen::Matrix<double,1,1> valueM = s.transpose() * M * s + C * s * 2.0;
       double value = valueM[0] + gamma;
       
       std::vector<std::pair<double,Eigen::Vector4d>,Eigen::aligned_allocator< std::pair<double,Eigen::Vector4d> > >::iterator
diff --git a/src/math/roots.cpp b/src/math/roots.cpp
index f87eb79d..c31b27cf 100644
--- a/src/math/roots.cpp
+++ b/src/math/roots.cpp
@@ -31,6 +31,7 @@
 
 #include <opengv/math/roots.hpp>
 #include <complex>
+#include <math.h>
 
 std::vector<double>
 opengv::math::o3_roots( const std::vector<double> & p )