diff --git a/lib/wx/api_gen/wx_gen_nif.erl b/lib/wx/api_gen/wx_gen_nif.erl
index bf67205275f..dc77e53cfdb 100644
--- a/lib/wx/api_gen/wx_gen_nif.erl
+++ b/lib/wx/api_gen/wx_gen_nif.erl
@@ -388,6 +388,7 @@ gen_method(CName,  M=#method{name=N,params=Ps0,type=T,method_type=MT,id=MethodId
     Opts = [Opt || Opt = #param{def=Def,in=In,where=Where} <- Ps2,
 		   Def =/= none, In =/= false, Where =/= c],
     decode_options(Opts, Argc),
+
     case gen_util:get_hook(c, M#method.pre_hook) of
 	ignore -> skip;
 	Pre -> w(" ~s;~n", [Pre])
@@ -542,6 +543,23 @@ decode_opt(#param{name=Name,type=Type}) ->
 decode_arguments(Ps0) ->
     lists:mapfoldl(fun decode_arg/2,0,Ps0).
 
+%% Postpone alloc and memcpy until after all Badarg execeptions
+%% so we don't leak memory in case of later badarg
+copy_arguments([#param{where=Where, in=In, def=none, name=N, type=Type}|Rest])
+  when Where =/= erl, Where =/= c, In =/= false ->
+    case Type of
+        #type{base = binary, by_val=copy} ->
+            w("  ~s = (unsigned char *) malloc(~s_bin.size);\n", [N,N]),
+            w("  memcpy(~s,~s_bin.data,~s_bin.size);\n", [N,N,N]);
+        _ ->
+            ignore
+    end,
+    copy_arguments(Rest);
+copy_arguments([_|Rest]) ->
+    copy_arguments(Rest);
+copy_arguments([]) ->
+    ok.
+
 store_free(N) ->
     case get(free_args) of
         undefined -> put(free_args, [N]);
@@ -710,9 +728,10 @@ decode_arg(N,#type{name=Type,base=binary,mod=Mod0,by_val=Copy},Arg,Argc) ->
     w("  ErlNifBinary ~s_bin;~n",[N]),
     w("  if(!enif_inspect_binary(env, ~s, &~s_bin)) ~s;~n",[Argc, N, badarg(N)]),
     case Copy of
-        copy ->
-            w("  ~s = (unsigned char *) malloc(~s_bin.size);\n", [N,N]),
-            w("  memcpy(~s,~s_bin.data,~s_bin.size);\n", [N,N,N]);
+        copy -> %% postpone see copy_arguments
+            %% w("  ~s = (unsigned char *) malloc(~s_bin.size);\n", [N,N]),
+            %% w("  memcpy(~s,~s_bin.data,~s_bin.size);\n", [N,N,N]);
+            ok;
         _ ->
             w("  ~s = (~s~s*) ~s_bin.data;~n", [N,Mod,Type,N])
     end;
@@ -797,6 +816,8 @@ call_wx(_N,{constructor,_},#type{base={class,RClass}},Ps) ->
 		false -> RClass
 	    end,
 
+    copy_arguments(Ps),
+
     case [P || #param{type={merged,_}}=P <- Ps] of
         [] ->
             w("  ~s * Result = new ~s(~s);~n",
@@ -838,6 +859,7 @@ call_wx(_N,{constructor,_},#type{base={class,RClass}},Ps) ->
 call_wx(N,{member,_},Type,Ps0) ->
     {Beg,End} = return_res(Type),
     w("  if(!This) throw wxe_badarg(\"This\");~n",[]),
+    copy_arguments(Ps0),
     Ps = filter(Ps0),
     case [P || #param{type={merged,_}}=P <- Ps] of
         [] ->
@@ -858,6 +880,7 @@ call_wx(N,{member,_},Type,Ps0) ->
 call_wx(N,{static,Class},Type,Ps) ->
     {Beg,End} = return_res(Type),
     #class{parent=Parent} = get({class,Class}),
+    copy_arguments(Ps),
     case [P || #param{type={merged,_}}=P <- Ps] of
         [] when Parent =:= "static" ->
 	    w("  ~s::~s(~s)~s;~n",[Beg,N,args(fun call_arg/1, ",",filter(Ps)),End]);
diff --git a/lib/wx/c_src/gen/wxe_wrapper_4.cpp b/lib/wx/c_src/gen/wxe_wrapper_4.cpp
index ac8bf918e9e..45cbc77e490 100644
--- a/lib/wx/c_src/gen/wxe_wrapper_4.cpp
+++ b/lib/wx/c_src/gen/wxe_wrapper_4.cpp
@@ -1293,11 +1293,11 @@ void wxImage_new_4(WxeApp *app, wxeMemEnv *memenv, wxeCommand& Ecmd)
   unsigned char * data;
   ErlNifBinary data_bin;
   if(!enif_inspect_binary(env, argv[2], &data_bin)) Badarg("data");
-  data = (unsigned char *) malloc(data_bin.size);
-  memcpy(data,data_bin.data,data_bin.size);
   unsigned char * alpha;
   ErlNifBinary alpha_bin;
   if(!enif_inspect_binary(env, argv[3], &alpha_bin)) Badarg("alpha");
+  data = (unsigned char *) malloc(data_bin.size);
+  memcpy(data,data_bin.data,data_bin.size);
   alpha = (unsigned char *) malloc(alpha_bin.size);
   memcpy(alpha,alpha_bin.data,alpha_bin.size);
   wxImage * Result = new EwxImage(width,height,data,alpha);
@@ -1323,11 +1323,11 @@ void wxImage_new_3_3(WxeApp *app, wxeMemEnv *memenv, wxeCommand& Ecmd)
   unsigned char * data;
   ErlNifBinary data_bin;
   if(!enif_inspect_binary(env, argv[1], &data_bin)) Badarg("data");
-  data = (unsigned char *) malloc(data_bin.size);
-  memcpy(data,data_bin.data,data_bin.size);
   unsigned char * alpha;
   ErlNifBinary alpha_bin;
   if(!enif_inspect_binary(env, argv[2], &alpha_bin)) Badarg("alpha");
+  data = (unsigned char *) malloc(data_bin.size);
+  memcpy(data,data_bin.data,data_bin.size);
   alpha = (unsigned char *) malloc(alpha_bin.size);
   memcpy(alpha,alpha_bin.data,alpha_bin.size);
   wxImage * Result = new EwxImage(sz,data,alpha);
@@ -1658,9 +1658,9 @@ void wxImage_Create_3_0(WxeApp *app, wxeMemEnv *memenv, wxeCommand& Ecmd)
   unsigned char * data;
   ErlNifBinary data_bin;
   if(!enif_inspect_binary(env, argv[3], &data_bin)) Badarg("data");
+  if(!This) throw wxe_badarg("This");
   data = (unsigned char *) malloc(data_bin.size);
   memcpy(data,data_bin.data,data_bin.size);
-  if(!This) throw wxe_badarg("This");
   bool Result = This->Create(width,height,data);
   wxeReturn rt = wxeReturn(memenv, Ecmd.caller, true);
   rt.send(  rt.make_bool(Result));
@@ -1685,9 +1685,9 @@ void wxImage_Create_2_0(WxeApp *app, wxeMemEnv *memenv, wxeCommand& Ecmd)
   unsigned char * data;
   ErlNifBinary data_bin;
   if(!enif_inspect_binary(env, argv[2], &data_bin)) Badarg("data");
+  if(!This) throw wxe_badarg("This");
   data = (unsigned char *) malloc(data_bin.size);
   memcpy(data,data_bin.data,data_bin.size);
-  if(!This) throw wxe_badarg("This");
   bool Result = This->Create(sz,data);
   wxeReturn rt = wxeReturn(memenv, Ecmd.caller, true);
   rt.send(  rt.make_bool(Result));
@@ -1708,14 +1708,14 @@ void wxImage_Create_4(WxeApp *app, wxeMemEnv *memenv, wxeCommand& Ecmd)
   unsigned char * data;
   ErlNifBinary data_bin;
   if(!enif_inspect_binary(env, argv[3], &data_bin)) Badarg("data");
-  data = (unsigned char *) malloc(data_bin.size);
-  memcpy(data,data_bin.data,data_bin.size);
   unsigned char * alpha;
   ErlNifBinary alpha_bin;
   if(!enif_inspect_binary(env, argv[4], &alpha_bin)) Badarg("alpha");
+  if(!This) throw wxe_badarg("This");
+  data = (unsigned char *) malloc(data_bin.size);
+  memcpy(data,data_bin.data,data_bin.size);
   alpha = (unsigned char *) malloc(alpha_bin.size);
   memcpy(alpha,alpha_bin.data,alpha_bin.size);
-  if(!This) throw wxe_badarg("This");
   bool Result = This->Create(width,height,data,alpha);
   wxeReturn rt = wxeReturn(memenv, Ecmd.caller, true);
   rt.send(  rt.make_bool(Result));
@@ -1740,14 +1740,14 @@ void wxImage_Create_3_2(WxeApp *app, wxeMemEnv *memenv, wxeCommand& Ecmd)
   unsigned char * data;
   ErlNifBinary data_bin;
   if(!enif_inspect_binary(env, argv[2], &data_bin)) Badarg("data");
-  data = (unsigned char *) malloc(data_bin.size);
-  memcpy(data,data_bin.data,data_bin.size);
   unsigned char * alpha;
   ErlNifBinary alpha_bin;
   if(!enif_inspect_binary(env, argv[3], &alpha_bin)) Badarg("alpha");
+  if(!This) throw wxe_badarg("This");
+  data = (unsigned char *) malloc(data_bin.size);
+  memcpy(data,data_bin.data,data_bin.size);
   alpha = (unsigned char *) malloc(alpha_bin.size);
   memcpy(alpha,alpha_bin.data,alpha_bin.size);
-  if(!This) throw wxe_badarg("This");
   bool Result = This->Create(sz,data,alpha);
   wxeReturn rt = wxeReturn(memenv, Ecmd.caller, true);
   rt.send(  rt.make_bool(Result));
@@ -2675,9 +2675,9 @@ void wxImage_SetAlpha_1(WxeApp *app, wxeMemEnv *memenv, wxeCommand& Ecmd)
   unsigned char * alpha;
   ErlNifBinary alpha_bin;
   if(!enif_inspect_binary(env, argv[1], &alpha_bin)) Badarg("alpha");
+  if(!This) throw wxe_badarg("This");
   alpha = (unsigned char *) malloc(alpha_bin.size);
   memcpy(alpha,alpha_bin.data,alpha_bin.size);
-  if(!This) throw wxe_badarg("This");
   This->SetAlpha(alpha);
 
 }
@@ -2710,9 +2710,9 @@ void wxImage_SetData_1(WxeApp *app, wxeMemEnv *memenv, wxeCommand& Ecmd)
   unsigned char * data;
   ErlNifBinary data_bin;
   if(!enif_inspect_binary(env, argv[1], &data_bin)) Badarg("data");
+  if(!This) throw wxe_badarg("This");
   data = (unsigned char *) malloc(data_bin.size);
   memcpy(data,data_bin.data,data_bin.size);
-  if(!This) throw wxe_badarg("This");
   This->SetData(data);
 
 }
@@ -2727,13 +2727,13 @@ void wxImage_SetData_3(WxeApp *app, wxeMemEnv *memenv, wxeCommand& Ecmd)
   unsigned char * data;
   ErlNifBinary data_bin;
   if(!enif_inspect_binary(env, argv[1], &data_bin)) Badarg("data");
-  data = (unsigned char *) malloc(data_bin.size);
-  memcpy(data,data_bin.data,data_bin.size);
   int new_width;
   if(!enif_get_int(env, argv[2], &new_width)) Badarg("new_width"); // int
   int new_height;
   if(!enif_get_int(env, argv[3], &new_height)) Badarg("new_height"); // int
   if(!This) throw wxe_badarg("This");
+  data = (unsigned char *) malloc(data_bin.size);
+  memcpy(data,data_bin.data,data_bin.size);
   This->SetData(data,new_width,new_height);
 
 }
diff --git a/lib/wx/c_src/wxe_gl.cpp b/lib/wx/c_src/wxe_gl.cpp
index a0b13aae62a..12eed621f13 100644
--- a/lib/wx/c_src/wxe_gl.cpp
+++ b/lib/wx/c_src/wxe_gl.cpp
@@ -75,15 +75,19 @@ void setActiveGL(wxeMemEnv *memenv, ErlNifPid caller, wxGLCanvas *canvas, wxGLCo
 {
   ErlNifUInt64 callId = wxe_make_hash(memenv->tmp_env, &caller);
   wxe_glc * entry = glc[callId];
+
   gl_active_index = callId;
   gl_active_pid = caller;
 
   if(!entry) {
-    entry = (wxe_glc *) malloc(sizeof(wxe_glc));
-    entry->canvas = NULL;
-    entry->context = NULL;
+    if(canvas && context) {
+      entry = (wxe_glc *) malloc(sizeof(wxe_glc));
+      entry->canvas = NULL;
+      entry->context = NULL;
+    }
+    else  // canvas or context are NULL ignore
+      return;
   }
-
   if(entry->canvas == canvas && entry->context == context)
     return;
 
diff --git a/lib/wx/c_src/wxe_return.cpp b/lib/wx/c_src/wxe_return.cpp
index d2fd9b1b14d..f4c9ee5342e 100644
--- a/lib/wx/c_src/wxe_return.cpp
+++ b/lib/wx/c_src/wxe_return.cpp
@@ -233,7 +233,7 @@ ERL_NIF_TERM wxeReturn::make_array_objs(wxAuiPaneInfoArray& arr, WxeApp *app, co
   ERL_NIF_TERM head, tail;
   ERL_NIF_TERM class_name = enif_make_atom(env, cname);
   tail = enif_make_list(env, 0);
-  for(unsigned int i = arr.GetCount() -1; i >= 0; i--) {
+  for(ErlNifSInt64 i = arr.GetCount() -1; i >= 0; i--) {
     head = make_ref(app->getRef((void *) &arr.Item(i),memenv), class_name);
     tail = enif_make_list_cell(env, head, tail);
   }
@@ -245,7 +245,7 @@ ERL_NIF_TERM wxeReturn::make_array_objs(wxArrayTreeItemIds& arr)
 {
   ERL_NIF_TERM head, tail;
   tail = enif_make_list(env, 0);
-  for(unsigned int i = arr.GetCount() -1; i >= 0; i--) {
+  for(ErlNifSInt64 i = arr.GetCount() -1; i >= 0; i--) {
     head = make((wxUIntPtr *) arr[i].m_pItem);
     tail = enif_make_list_cell(env, head, tail);
   }
@@ -257,7 +257,7 @@ ERL_NIF_TERM wxeReturn::make_array_objs(wxGridCellCoordsArray& arr)
 {
   ERL_NIF_TERM head, tail;
   tail = enif_make_list(env, 0);
-  for(unsigned int i = arr.GetCount() -1; i >= 0; i--) {
+  for(ErlNifSInt64 i = arr.GetCount() -1; i >= 0; i--) {
     head = make(arr[i]);
     tail = enif_make_list_cell(env, head, tail);
   }
diff --git a/lib/wx/test/wx_class_SUITE.erl b/lib/wx/test/wx_class_SUITE.erl
index f18d2eefe04..70ee2f46ce3 100644
--- a/lib/wx/test/wx_class_SUITE.erl
+++ b/lib/wx/test/wx_class_SUITE.erl
@@ -150,6 +150,9 @@ treeCtrl(Config) ->
     ?m({0, _}, wxTreeCtrl:hitTest(Tree, {X0+W0+W0, Y0+H0+4*H0})),
     ?m(false, wxTreeCtrl:isTreeItemIdOk(0)),
 
+    {N, Sels} = wxTreeCtrl:getSelections(Tree),
+    N = length(Sels),
+
     wxFrame:connect(Tree, command_tree_item_expanded),
     wxFrame:connect(Tree, command_tree_item_collapsed),
     wxFrame:connect(Frame, close_window),