diff --git a/src/msw/radiobox.cpp b/src/msw/radiobox.cpp
index fe2d803e2c..0bdbdb136a 100644
--- a/src/msw/radiobox.cpp
+++ b/src/msw/radiobox.cpp
@@ -368,9 +368,9 @@ void wxRadioBox::DoSetSize(int x, int y, int width, int height, int sizeFlags)
     int xx = x;
     int yy = y;
 
-    if (x == -1 || (sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
+    if (x == -1 && !(sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
         xx = currentX;
-    if (y == -1 || (sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
+    if (y == -1 && !(sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
         yy = currentY;
 
 #if RADIOBTN_PARENT_IS_RADIOBOX
diff --git a/src/msw/slider95.cpp b/src/msw/slider95.cpp
index 10a12ac3ef..ef1e073fbf 100644
--- a/src/msw/slider95.cpp
+++ b/src/msw/slider95.cpp
@@ -353,9 +353,9 @@ void wxSlider95::DoSetSize(int x, int y, int width, int height, int sizeFlags)
 
   int currentX, currentY;
   GetPosition(&currentX, &currentY);
-  if (x == -1 || (sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
+  if (x == -1 && !(sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
     x1 = currentX;
-  if (y == -1 || (sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
+  if (y == -1 && !(sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
     y1 = currentY;
 
   AdjustForParentClientOrigin(x1, y1, sizeFlags);
diff --git a/src/msw/slidrmsw.cpp b/src/msw/slidrmsw.cpp
index a915542d62..1bb9b0876d 100644
--- a/src/msw/slidrmsw.cpp
+++ b/src/msw/slidrmsw.cpp
@@ -324,9 +324,9 @@ void wxSliderMSW::DoSetSize(int x, int y, int width, int height, int sizeFlags)
 
   int currentX, currentY;
   GetPosition(&currentX, &currentY);
-  if (x == -1 || (sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
+  if (x == -1 && !(sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
     x1 = currentX;
-  if (y == -1 || (sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
+  if (y == -1 && !(sizeFlags & wxSIZE_ALLOW_MINUS_ONE))
     y1 = currentY;
 
   AdjustForParentClientOrigin(x1, y1, sizeFlags);