Fix missing definition of std::hash<wxPoint> when using wxWidgets 3.1.x

it was not compiled for wxWidgets 3.1.x, but it does not exist in 3.1.x

common/common.cpp

@@ -1,7 +1,7 @@
 /*
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
- * Copyright (C) 2014-2018 Jean-Pierre Charras, jp.charras at wanadoo.fr
+ * Copyright (C) 2014-2019 Jean-Pierre Charras, jp.charras at wanadoo.fr
  * Copyright (C) 2008 Wayne Stambaugh <stambaughw@gmail.com>
  * Copyright (C) 1992-2019 KiCad Developers, see AUTHORS.txt for contributors.
  *
@@ -167,12 +167,12 @@ void SelectReferenceNumber( wxTextEntry* aTextEntry )
     {
         wxString num = ref;
 
-        while( !num.IsEmpty() && ( !wxIsdigit( num.Last() ) || !wxIsdigit( num.GetChar( 0 ) ) ) )
+        while( !num.IsEmpty() && ( !isdigit( num.Last() ) || !isdigit( num.GetChar( 0 ) ) ) )
         {
-            if( !wxIsdigit( num.Last() ) )
+            if( !isdigit( num.Last() ) )
                 num.RemoveLast();
 
-            if( !wxIsdigit( num.GetChar ( 0 ) ) )
+            if( !isdigit( num.GetChar ( 0 ) ) )
                 num = num.Right( num.Length() - 1);
         }
 
@@ -591,8 +591,13 @@ size_t std::hash<wxString>::operator()( const wxString& s ) const
 }
 #endif
 
+#ifdef USE_KICAD_WXPOINT_LESS_AND_HASH
+size_t std::hash<wxPoint>::operator() ( const wxPoint& k ) const
+{
+    return ( ( std::hash<int>()( k.x )
+             ^ ( std::hash<int>()( k.y ) << 1 ) ) >> 1 );
+}
 
-#ifdef USE_KICAD_WXPOINT_LESS
 bool std::less<wxPoint>::operator()( const wxPoint& aA, const wxPoint& aB ) const
 {
     if( aA.x == aB.x )

include/common.h

@@ -1,10 +1,10 @@
 /*
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
- * Copyright (C) 2014-2017 Jean-Pierre Charras, jp.charras at wanadoo.fr
+ * Copyright (C) 2014-2019 Jean-Pierre Charras, jp.charras at wanadoo.fr
  * Copyright (C) 2007-2015 SoftPLC Corporation, Dick Hollenbeck <dick@softplc.com>
  * Copyright (C) 2008 Wayne Stambaugh <stambaughw@gmail.com>
- * Copyright (C) 1992-2018 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 1992-2019 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -376,7 +376,15 @@ namespace std
 #endif
 
 /// Required to use wxPoint as key type in maps
-#define USE_KICAD_WXPOINT_LESS     // for common.cpp
+#define USE_KICAD_WXPOINT_LESS_AND_HASH // for common.cpp
+namespace std
+{
+    template <> struct hash<wxPoint>
+    {
+        size_t operator() ( const wxPoint& k ) const;
+    };
+}
+
 namespace std
 {
     template<> struct less<wxPoint>