diff --git a/include/fctsys.h b/include/fctsys.h
index 8225dfd0f3..42e8742e08 100644
--- a/include/fctsys.h
+++ b/include/fctsys.h
@@ -12,23 +12,23 @@
 #endif
 
 // for all others, include the necessary headers (this file is usually all you
-// need because it includes almost all "standard" wxWindows headers
+// need because it includes almost all "standard" wxWidgetss headers
 #ifndef WX_PRECOMP
 #include <wx/wx.h>
 #endif
 
-/*
- * FIXME: This appears to already be included in the OSX build of wxWidgets.
- *        Will someone with OSX please remove this and see if it compiles.
+/**
+ * @note This appears to already be included in the OSX build of wxWidgets.
+ *       Will someone with OSX please remove this and see if it compiles?
  */
 #ifdef __WXMAC__
 #include <Carbon/Carbon.h>
 #endif
 
-#ifndef M_PI
-#define M_PI 3.141592653
-#endif
-
+/**
+ * @note Shouldn't we be using wxFileName::GetPathSeparator() instead of the following code
+ *       for improved portability?
+ */
 #ifdef __WINDOWS__
 #define DIR_SEP        '\\'
 #define STRING_DIR_SEP wxT( "\\" )
@@ -37,6 +37,12 @@
 #define STRING_DIR_SEP wxT( "/" )
 #endif
 
+/**
+ * @note Do we really need these defined again?
+ */
+#define UNIX_STRING_DIR_SEP wxT( "/" )
+#define WIN_STRING_DIR_SEP  wxT( "\\" )
+
 #ifdef DEBUG
 #define D(x)        x
 #else
@@ -63,18 +69,14 @@ template <typename T> inline const T& Clamp( const T& lower, const T& value, con
     return value;
 }
 
-#define UNIX_STRING_DIR_SEP wxT( "/" )
-#define WIN_STRING_DIR_SEP  wxT( "\\" )
-
 #define USE_RESIZE_BORDER
 #if defined(__UNIX__) || defined(USE_RESIZE_BORDER)
-#define MAYBE_RESIZE_BORDER wxRESIZE_BORDER   // linux users like resizeable
-                                              // borders
+#define MAYBE_RESIZE_BORDER wxRESIZE_BORDER   // Linux users like resizeable borders
 #else
 #define MAYBE_RESIZE_BORDER 0                 // no resizeable border
 #endif
 
-// wxNullPtr is not defined prior to wxWidget 2.9.0.
+// wxNullPtr is not defined prior to wxWidgets 2.9.0.
 #if !wxCHECK_VERSION( 2, 9, 0 )
 #define wxNullPtr ((void *)NULL)
 #endif
diff --git a/pcbnew/muonde.cpp b/pcbnew/muonde.cpp
index a25991594b..da2d7477fb 100644
--- a/pcbnew/muonde.cpp
+++ b/pcbnew/muonde.cpp
@@ -320,7 +320,7 @@ static void gen_arc( std::vector <wxPoint>& aBuffer,
     if( seg_count == 0 )
         seg_count = 1;
 
-    double increment_angle = (double) a_ArcAngle * 3.14159 / 1800 / seg_count;
+    double increment_angle = (double) a_ArcAngle * M_PI / 1800 / seg_count;
 
     // Creates nb_seg point to approximate arc by segments:
     for( int ii = 1; ii <= seg_count; ii++ )
diff --git a/pcbnew/zones_convert_brd_items_to_polygons_with_Boost.cpp b/pcbnew/zones_convert_brd_items_to_polygons_with_Boost.cpp
index 2933d1cf56..fedbe05e28 100644
--- a/pcbnew/zones_convert_brd_items_to_polygons_with_Boost.cpp
+++ b/pcbnew/zones_convert_brd_items_to_polygons_with_Boost.cpp
@@ -137,7 +137,7 @@ void ZONE_CONTAINER::AddClearanceAreasPolygonsToPolysList( BOARD* aPcb )
      * For a circle the min radius is radius * cos( 2PI / s_CircleToSegmentsCount / 2)
      * s_Correction is 1 /cos( PI/s_CircleToSegmentsCount  )
      */
-    s_Correction = 1.0 / cos( 3.14159265 / s_CircleToSegmentsCount );
+    s_Correction = 1.0 / cos( M_PI / s_CircleToSegmentsCount );
 
     // This KI_POLYGON_SET is the area(s) to fill, with m_ZoneMinThickness/2
     KI_POLYGON_SET polyset_zone_solid_areas;