diff --git a/src/core/place.c b/src/core/place.c
index cab76993e..23eb68e7f 100644
--- a/src/core/place.c
+++ b/src/core/place.c
@@ -784,22 +784,22 @@ meta_window_place (MetaWindow        *window,
     {
       switch (window->type)
         {
-          /* Only accept USPosition on normal windows because the app is full
+          /* Only accept USER_POSITION on normal windows because the app is full
            * of shit claiming the user set -geometry for a dialog or dock
            */
         case META_WINDOW_NORMAL:
-          if (window->size_hints.flags & USPosition)
+          if (window->size_hints.flags & META_SIZE_HINTS_USER_POSITION)
             {
               /* don't constrain with placement algorithm */
               meta_topic (META_DEBUG_PLACEMENT,
-                          "Honoring USPosition for %s instead of using placement algorithm",
+                          "Honoring USER_POSITION for %s instead of using placement algorithm",
                           window->desc);
 
               goto done;
             }
           break;
 
-          /* Ignore even USPosition on dialogs, splashscreen */
+          /* Ignore even USER_POSITION on dialogs, splashscreen */
         case META_WINDOW_DIALOG:
         case META_WINDOW_MODAL_DIALOG:
         case META_WINDOW_SPLASHSCREEN:
@@ -819,10 +819,10 @@ meta_window_place (MetaWindow        *window,
 	case META_WINDOW_COMBO:
 	case META_WINDOW_DND:
 	case META_WINDOW_OVERRIDE_OTHER:
-          if (window->size_hints.flags & PPosition)
+          if (window->size_hints.flags & META_SIZE_HINTS_PROGRAM_POSITION)
             {
               meta_topic (META_DEBUG_PLACEMENT,
-                          "Not placing non-normal non-dialog window with PPosition set");
+                          "Not placing non-normal non-dialog window with PROGRAM_POSITION set");
               goto done;
             }
           break;
@@ -832,11 +832,11 @@ meta_window_place (MetaWindow        *window,
     {
       /* workarounds enabled */
 
-      if ((window->size_hints.flags & PPosition) ||
-          (window->size_hints.flags & USPosition))
+      if ((window->size_hints.flags & META_SIZE_HINTS_PROGRAM_POSITION) ||
+          (window->size_hints.flags & META_SIZE_HINTS_USER_POSITION))
         {
           meta_topic (META_DEBUG_PLACEMENT,
-                      "Not placing window with PPosition or USPosition set");
+                      "Not placing window with PROGRAM_POSITION or USER_POSITION set");
           avoid_being_obscured_as_second_modal_dialog (window, &x, &y);
           goto done;
         }
diff --git a/src/core/window-private.h b/src/core/window-private.h
index bd27272af..ab3b1f667 100644
--- a/src/core/window-private.h
+++ b/src/core/window-private.h
@@ -164,6 +164,49 @@ typedef enum
   META_EDGE_RESISTANCE_WINDOWS     = 1 << 2,
 } MetaEdgeResistanceFlags;
 
+typedef enum
+{
+  /* Equivalent to USPosition */
+  META_SIZE_HINTS_USER_POSITION = (1L << 0),
+  /* Equivalent to USSize */
+  META_SIZE_HINTS_USER_SIZE = (1L << 1),
+  /* Equivalent to PPosition */
+  META_SIZE_HINTS_PROGRAM_POSITION = (1L << 2),
+  /* Equivalent to PSize */
+  META_SIZE_HINTS_PROGRAM_SIZE = (1L << 3),
+  /* Equivalent to PMinSize */
+  META_SIZE_HINTS_PROGRAM_MIN_SIZE = (1L << 4),
+  /* Equivalent to PMaxSize */
+  META_SIZE_HINTS_PROGRAM_MAX_SIZE = (1L << 5),
+  /* Equivalent to PResizeInc */
+  META_SIZE_HINTS_PROGRAM_RESIZE_INCREMENTS = (1L << 6),
+  /* Equivalent to PAspect */
+  META_SIZE_HINTS_PROGRAM_ASPECT = (1L << 7),
+  /* Equivalent to PBaseSize */
+  META_SIZE_HINTS_PROGRAM_BASE_SIZE = (1L << 8),
+  /* Equivalent to PWinGravity */
+  META_SIZE_HINTS_PROGRAM_WIN_GRAVITY = (1L << 9),
+} MetaSizeHintsFlags;
+
+/**
+ * A copy of XSizeHints that is meant to stay ABI compatible
+ * with XSizeHints for x11 code paths usages
+ */
+typedef struct _MetaSizeHints {
+  long flags; /* MetaSizeHintsFlags but kept as long to be able to cast between XSizeHints and MetaSizeHints */
+  int x, y;
+  int width, height;
+  int min_width, min_height;
+  int max_width, max_height;
+  int width_inc, height_inc;
+  struct {
+    int x;  /* numerator */
+    int y;  /* denominator */
+  } min_aspect, max_aspect;
+  int base_width, base_height;
+  int win_gravity;
+} MetaSizeHints;
+
 struct _MetaWindow
 {
   GObject parent_instance;
@@ -300,7 +343,7 @@ struct _MetaWindow
   MtkRectangle icon_geometry;
 
   /* x/y/w/h here get filled with ConfigureRequest values */
-  XSizeHints size_hints;
+  MetaSizeHints size_hints;
 
   /* Managed by stack.c */
   MetaStackLayer layer;
diff --git a/src/core/window.c b/src/core/window.c
index fe79b86fb..c86431756 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -2539,8 +2539,8 @@ meta_window_unminimize (MetaWindow  *window)
 }
 
 static void
-ensure_size_hints_satisfied (MtkRectangle     *rect,
-                             const XSizeHints *size_hints)
+ensure_size_hints_satisfied (MtkRectangle        *rect,
+                             const MetaSizeHints *size_hints)
 {
   int minw, minh, maxw, maxh;   /* min/max width/height                      */
   int basew, baseh, winc, hinc; /* base width/height, width/height increment */
diff --git a/src/wayland/meta-window-wayland.c b/src/wayland/meta-window-wayland.c
index 4d3f85ca1..354183106 100644
--- a/src/wayland/meta-window-wayland.c
+++ b/src/wayland/meta-window-wayland.c
@@ -1320,7 +1320,7 @@ meta_window_wayland_set_min_size (MetaWindow *window,
     {
       window->size_hints.min_width = 0;
       window->size_hints.min_height = 0;
-      window->size_hints.flags &= ~PMinSize;
+      window->size_hints.flags &= ~META_SIZE_HINTS_PROGRAM_MIN_SIZE;
 
       return;
     }
@@ -1335,7 +1335,7 @@ meta_window_wayland_set_min_size (MetaWindow *window,
 
   window->size_hints.min_width = (int) MIN (new_width, G_MAXINT);
   window->size_hints.min_height = (int) MIN (new_height, G_MAXINT);
-  window->size_hints.flags |= PMinSize;
+  window->size_hints.flags |= META_SIZE_HINTS_PROGRAM_MIN_SIZE;
 }
 
 void
@@ -1354,7 +1354,7 @@ meta_window_wayland_set_max_size (MetaWindow *window,
     {
       window->size_hints.max_width = G_MAXINT;
       window->size_hints.max_height = G_MAXINT;
-      window->size_hints.flags &= ~PMaxSize;
+      window->size_hints.flags &= ~META_SIZE_HINTS_PROGRAM_MAX_SIZE;
 
       return;
     }
@@ -1371,7 +1371,7 @@ meta_window_wayland_set_max_size (MetaWindow *window,
                                         new_width : G_MAXINT);
   window->size_hints.max_height = (int)  ((new_height > 0 && new_height < G_MAXINT) ?
                                           new_height : G_MAXINT);
-  window->size_hints.flags |= PMaxSize;
+  window->size_hints.flags |= META_SIZE_HINTS_PROGRAM_MAX_SIZE;
 }
 
 void
@@ -1382,7 +1382,7 @@ meta_window_wayland_get_min_size (MetaWindow *window,
   gint64 current_width, current_height;
   float scale;
 
-  if (!(window->size_hints.flags & PMinSize))
+  if (!(window->size_hints.flags & META_SIZE_HINTS_PROGRAM_MIN_SIZE))
     {
       /* Zero means unlimited */
       *width = 0;
@@ -1414,7 +1414,7 @@ meta_window_wayland_get_max_size (MetaWindow *window,
   gint64 current_height = 0;
   float scale;
 
-  if (!(window->size_hints.flags & PMaxSize))
+  if (!(window->size_hints.flags & META_SIZE_HINTS_PROGRAM_MAX_SIZE))
     {
       /* Zero means unlimited */
       *width = 0;
diff --git a/src/x11/window-props.c b/src/x11/window-props.c
index 73f80395b..c18b3eab5 100644
--- a/src/x11/window-props.c
+++ b/src/x11/window-props.c
@@ -1085,132 +1085,132 @@ reload_update_counter (MetaWindow    *window,
   (FLAG_TOGGLED_ON(old,new,flag) || FLAG_TOGGLED_OFF(old,new,flag))
 
 static void
-spew_size_hints_differences (const XSizeHints *old,
-                             const XSizeHints *new)
+spew_size_hints_differences (const MetaSizeHints *old,
+                             const MetaSizeHints *new)
 {
-  if (FLAG_CHANGED (old, new, USPosition))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: USPosition now %s",
-                FLAG_TOGGLED_ON (old, new, USPosition) ? "set" : "unset");
-  if (FLAG_CHANGED (old, new, USSize))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: USSize now %s",
-                FLAG_TOGGLED_ON (old, new, USSize) ? "set" : "unset");
-  if (FLAG_CHANGED (old, new, PPosition))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PPosition now %s",
-                FLAG_TOGGLED_ON (old, new, PPosition) ? "set" : "unset");
-  if (FLAG_CHANGED (old, new, PSize))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PSize now %s",
-                FLAG_TOGGLED_ON (old, new, PSize) ? "set" : "unset");
-  if (FLAG_CHANGED (old, new, PMinSize))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PMinSize now %s (%d x %d -> %d x %d)",
-                FLAG_TOGGLED_ON (old, new, PMinSize) ? "set" : "unset",
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_USER_POSITION))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: USER_POSITION now %s",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_USER_POSITION) ? "set" : "unset");
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_USER_SIZE))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: USER_SIZE now %s",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_USER_SIZE) ? "set" : "unset");
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_PROGRAM_POSITION))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PROGRAM_POSITION now %s",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_POSITION) ? "set" : "unset");
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_PROGRAM_SIZE))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PROGRAM_SIZE now %s",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_SIZE) ? "set" : "unset");
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_PROGRAM_MIN_SIZE))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PROGRAM_MIN_SIZE now %s (%d x %d -> %d x %d)",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_MIN_SIZE) ? "set" : "unset",
                 old->min_width, old->min_height,
                 new->min_width, new->min_height);
-  if (FLAG_CHANGED (old, new, PMaxSize))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PMaxSize now %s (%d x %d -> %d x %d)",
-                FLAG_TOGGLED_ON (old, new, PMaxSize) ? "set" : "unset",
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_PROGRAM_MAX_SIZE))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PROGRAM_MAX_SIZE now %s (%d x %d -> %d x %d)",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_MAX_SIZE) ? "set" : "unset",
                 old->max_width, old->max_height,
                 new->max_width, new->max_height);
-  if (FLAG_CHANGED (old, new, PResizeInc))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PResizeInc now %s (width_inc %d -> %d height_inc %d -> %d)",
-                FLAG_TOGGLED_ON (old, new, PResizeInc) ? "set" : "unset",
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_PROGRAM_RESIZE_INCREMENTS))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PROGRAM_RESIZE_INCREMENTS now %s (width_inc %d -> %d height_inc %d -> %d)",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_RESIZE_INCREMENTS) ? "set" : "unset",
                 old->width_inc, new->width_inc,
                 old->height_inc, new->height_inc);
-  if (FLAG_CHANGED (old, new, PAspect))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PAspect now %s (min %d/%d -> %d/%d max %d/%d -> %d/%d)",
-                FLAG_TOGGLED_ON (old, new, PAspect) ? "set" : "unset",
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_PROGRAM_ASPECT))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PROGRAM_ASPECT now %s (min %d/%d -> %d/%d max %d/%d -> %d/%d)",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_ASPECT) ? "set" : "unset",
                 old->min_aspect.x, old->min_aspect.y,
                 new->min_aspect.x, new->min_aspect.y,
                 old->max_aspect.x, old->max_aspect.y,
                 new->max_aspect.x, new->max_aspect.y);
-  if (FLAG_CHANGED (old, new, PBaseSize))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PBaseSize now %s (%d x %d -> %d x %d)",
-                FLAG_TOGGLED_ON (old, new, PBaseSize) ? "set" : "unset",
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_PROGRAM_BASE_SIZE))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PROGRAM_BASE_SIZE now %s (%d x %d -> %d x %d)",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_BASE_SIZE) ? "set" : "unset",
                 old->base_width, old->base_height,
                 new->base_width, new->base_height);
-  if (FLAG_CHANGED (old, new, PWinGravity))
-    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PWinGravity now %s  (%d -> %d)",
-                FLAG_TOGGLED_ON (old, new, PWinGravity) ? "set" : "unset",
+  if (FLAG_CHANGED (old, new, META_SIZE_HINTS_PROGRAM_WIN_GRAVITY))
+    meta_topic (META_DEBUG_GEOMETRY, "XSizeHints: PROGRAM_WIN_GRAVITY now %s  (%d -> %d)",
+                FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_WIN_GRAVITY) ? "set" : "unset",
                 old->win_gravity, new->win_gravity);
 }
 
 static gboolean
-hints_have_changed (const XSizeHints *old,
-                    const XSizeHints *new)
+hints_have_changed (const MetaSizeHints *old,
+                    const MetaSizeHints *new)
 {
   /* 1. Check if the relevant values have changed if the flag is set. */
 
-  if (FLAG_TOGGLED_ON (old, new, USPosition) ||
-      (FLAG_IS_ON (new, USPosition) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_USER_POSITION) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_USER_POSITION) &&
        (old->x != new->x ||
         old->y != new->y)))
     return TRUE;
 
-  if (FLAG_TOGGLED_ON (old, new, USSize) ||
-      (FLAG_IS_ON (new, USSize) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_USER_SIZE) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_USER_SIZE) &&
        (old->width != new->width ||
         old->height != new->height)))
     return TRUE;
 
-  if (FLAG_TOGGLED_ON (old, new, PPosition) ||
-      (FLAG_IS_ON (new, PPosition) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_POSITION) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_PROGRAM_POSITION) &&
        (old->x != new->x ||
         old->y != new->y)))
     return TRUE;
 
-  if (FLAG_TOGGLED_ON (old, new, PSize) ||
-      (FLAG_IS_ON (new, PSize) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_SIZE) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_PROGRAM_SIZE) &&
        (old->width != new->width ||
         old->height != new->height)))
     return TRUE;
 
-  if (FLAG_TOGGLED_ON (old, new, PMinSize) ||
-      (FLAG_IS_ON (new, PMinSize) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_MIN_SIZE) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_PROGRAM_MIN_SIZE) &&
        (old->min_width != new->min_width ||
         old->min_height != new->min_height)))
     return TRUE;
 
-  if (FLAG_TOGGLED_ON (old, new, PMaxSize) ||
-      (FLAG_IS_ON (new, PMaxSize) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_MAX_SIZE) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_PROGRAM_MAX_SIZE) &&
        (old->max_width != new->max_width ||
         old->max_height != new->max_height)))
     return TRUE;
 
-  if (FLAG_TOGGLED_ON (old, new, PResizeInc) ||
-      (FLAG_IS_ON (new, PResizeInc) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_RESIZE_INCREMENTS) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_PROGRAM_RESIZE_INCREMENTS) &&
        (old->width_inc != new->width_inc ||
         old->height_inc != new->height_inc)))
     return TRUE;
 
-  if (FLAG_TOGGLED_ON (old, new, PAspect) ||
-      (FLAG_IS_ON (new, PAspect) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_ASPECT) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_PROGRAM_ASPECT) &&
        (old->min_aspect.x != new->min_aspect.x ||
         old->min_aspect.y != new->min_aspect.y ||
         old->max_aspect.x != new->max_aspect.x ||
         old->max_aspect.y != new->max_aspect.y)))
     return TRUE;
 
-  if (FLAG_TOGGLED_ON (old, new, PBaseSize) ||
-      (FLAG_IS_ON (new, PBaseSize) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_BASE_SIZE) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_PROGRAM_BASE_SIZE) &&
        (old->base_width != new->base_width ||
         old->base_height != new->base_height)))
     return TRUE;
 
-  if (FLAG_TOGGLED_ON (old, new, PWinGravity) ||
-      (FLAG_IS_ON (new, PWinGravity) &&
+  if (FLAG_TOGGLED_ON (old, new, META_SIZE_HINTS_PROGRAM_WIN_GRAVITY) ||
+      (FLAG_IS_ON (new, META_SIZE_HINTS_PROGRAM_WIN_GRAVITY) &&
        (old->win_gravity != new->win_gravity)))
     return TRUE;
 
   /* 2. Check if the flags have been unset. */
-  return FLAG_TOGGLED_OFF (old, new, USPosition) ||
-         FLAG_TOGGLED_OFF (old, new, USSize) ||
-         FLAG_TOGGLED_OFF (old, new, PPosition) ||
-         FLAG_TOGGLED_OFF (old, new, PSize) ||
-         FLAG_TOGGLED_OFF (old, new, PMinSize) ||
-         FLAG_TOGGLED_OFF (old, new, PMaxSize) ||
-         FLAG_TOGGLED_OFF (old, new, PResizeInc) ||
-         FLAG_TOGGLED_OFF (old, new, PAspect) ||
-         FLAG_TOGGLED_OFF (old, new, PBaseSize) ||
-         FLAG_TOGGLED_OFF (old, new, PWinGravity);
+  return FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_USER_POSITION) ||
+         FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_USER_POSITION) ||
+         FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_PROGRAM_POSITION) ||
+         FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_PROGRAM_SIZE) ||
+         FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_PROGRAM_MIN_SIZE) ||
+         FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_PROGRAM_MAX_SIZE) ||
+         FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_PROGRAM_RESIZE_INCREMENTS) ||
+         FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_PROGRAM_ASPECT) ||
+         FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_PROGRAM_BASE_SIZE) ||
+         FLAG_TOGGLED_OFF (old, new, META_SIZE_HINTS_PROGRAM_WIN_GRAVITY);
 }
 
 void
@@ -1245,7 +1245,7 @@ meta_set_normal_hints (MetaWindow *window,
    * as if flags were zero
    */
   if (hints)
-    window->size_hints = *hints;
+    window->size_hints = *(MetaSizeHints*)(hints);
   else
     window->size_hints.flags = 0;
 
@@ -1256,14 +1256,14 @@ meta_set_normal_hints (MetaWindow *window,
   window->size_hints.height = h;
 
   /* Get base size hints */
-  if (window->size_hints.flags & PBaseSize)
+  if (window->size_hints.flags & META_SIZE_HINTS_PROGRAM_BASE_SIZE)
     {
       meta_topic (META_DEBUG_GEOMETRY, "Window %s sets base size %d x %d",
                   window->desc,
                   window->size_hints.base_width,
                   window->size_hints.base_height);
     }
-  else if (window->size_hints.flags & PMinSize)
+  else if (window->size_hints.flags & META_SIZE_HINTS_PROGRAM_MIN_SIZE)
     {
       window->size_hints.base_width = window->size_hints.min_width;
       window->size_hints.base_height = window->size_hints.min_height;
@@ -1273,17 +1273,17 @@ meta_set_normal_hints (MetaWindow *window,
       window->size_hints.base_width = 0;
       window->size_hints.base_height = 0;
     }
-  window->size_hints.flags |= PBaseSize;
+  window->size_hints.flags |= META_SIZE_HINTS_PROGRAM_BASE_SIZE;
 
   /* Get min size hints */
-  if (window->size_hints.flags & PMinSize)
+  if (window->size_hints.flags & META_SIZE_HINTS_PROGRAM_MIN_SIZE)
     {
       meta_topic (META_DEBUG_GEOMETRY, "Window %s sets min size %d x %d",
                   window->desc,
                   window->size_hints.min_width,
                   window->size_hints.min_height);
     }
-  else if (window->size_hints.flags & PBaseSize)
+  else if (window->size_hints.flags & META_SIZE_HINTS_PROGRAM_BASE_SIZE)
     {
       window->size_hints.min_width = window->size_hints.base_width;
       window->size_hints.min_height = window->size_hints.base_height;
@@ -1293,10 +1293,10 @@ meta_set_normal_hints (MetaWindow *window,
       window->size_hints.min_width = 0;
       window->size_hints.min_height = 0;
     }
-  window->size_hints.flags |= PMinSize;
+  window->size_hints.flags |= META_SIZE_HINTS_PROGRAM_MIN_SIZE;
 
   /* Get max size hints */
-  if (window->size_hints.flags & PMaxSize)
+  if (window->size_hints.flags & META_SIZE_HINTS_PROGRAM_MAX_SIZE)
     {
       meta_topic (META_DEBUG_GEOMETRY, "Window %s sets max size %d x %d",
                   window->desc,
@@ -1307,11 +1307,11 @@ meta_set_normal_hints (MetaWindow *window,
     {
       window->size_hints.max_width = G_MAXINT;
       window->size_hints.max_height = G_MAXINT;
-      window->size_hints.flags |= PMaxSize;
+      window->size_hints.flags |= META_SIZE_HINTS_PROGRAM_MAX_SIZE;
     }
 
   /* Get resize increment hints */
-  if (window->size_hints.flags & PResizeInc)
+  if (window->size_hints.flags & META_SIZE_HINTS_PROGRAM_RESIZE_INCREMENTS)
     {
       meta_topic (META_DEBUG_GEOMETRY,
                   "Window %s sets resize width inc: %d height inc: %d",
@@ -1323,11 +1323,11 @@ meta_set_normal_hints (MetaWindow *window,
     {
       window->size_hints.width_inc = 1;
       window->size_hints.height_inc = 1;
-      window->size_hints.flags |= PResizeInc;
+      window->size_hints.flags |= META_SIZE_HINTS_PROGRAM_RESIZE_INCREMENTS;
     }
 
   /* Get aspect ratio hints */
-  if (window->size_hints.flags & PAspect)
+  if (window->size_hints.flags & META_SIZE_HINTS_PROGRAM_ASPECT)
     {
       meta_topic (META_DEBUG_GEOMETRY,
                   "Window %s sets min_aspect: %d/%d max_aspect: %d/%d",
@@ -1343,11 +1343,11 @@ meta_set_normal_hints (MetaWindow *window,
       window->size_hints.min_aspect.y = G_MAXINT;
       window->size_hints.max_aspect.x = G_MAXINT;
       window->size_hints.max_aspect.y = 1;
-      window->size_hints.flags |= PAspect;
+      window->size_hints.flags |= META_SIZE_HINTS_PROGRAM_ASPECT;
     }
 
   /* Get gravity hint */
-  if (window->size_hints.flags & PWinGravity)
+  if (window->size_hints.flags & META_SIZE_HINTS_PROGRAM_WIN_GRAVITY)
     {
       meta_topic (META_DEBUG_GEOMETRY, "Window %s sets gravity %d",
                   window->desc,
@@ -1359,7 +1359,7 @@ meta_set_normal_hints (MetaWindow *window,
                   "Window %s doesn't set gravity, using NW",
                   window->desc);
       window->size_hints.win_gravity = META_GRAVITY_NORTH_WEST;
-      window->size_hints.flags |= PWinGravity;
+      window->size_hints.flags |= META_SIZE_HINTS_PROGRAM_WIN_GRAVITY;
     }
 
   /*** Lots of sanity checking ***/
@@ -1562,7 +1562,7 @@ reload_normal_hints (MetaWindow    *window,
 {
   if (value->type != META_PROP_VALUE_INVALID)
     {
-      XSizeHints old_hints;
+      MetaSizeHints old_hints;
       gboolean hints_have_differences;
 
       meta_topic (META_DEBUG_GEOMETRY, "Updating WM_NORMAL_HINTS for %s", window->desc);
diff --git a/src/x11/window-x11.c b/src/x11/window-x11.c
index 42981584c..bd8528ced 100644
--- a/src/x11/window-x11.c
+++ b/src/x11/window-x11.c
@@ -1423,16 +1423,16 @@ meta_window_x11_move_resize_internal (MetaWindow                *window,
       !(need_resize_client || need_resize_frame))
     need_configure_notify = TRUE;
 
-  /* MapRequest events with a PPosition or UPosition hint with a frame
+  /* MapRequest events with a PROGRAM_POSITION or USER_POSITION hint with a frame
    * are moved by mutter without resizing; send a configure notify
    * in such cases.  See #322840.  (Note that window->constructing is
    * only true iff this call is due to a MapRequest, and when
-   * PPosition/UPosition hints aren't set, mutter seems to send a
+   * PROGRAM_POSITION/USER_POSITION hints aren't set, mutter seems to send a
    * ConfigureNotify anyway due to the above code.)
    */
   if (window->constructing && window->frame &&
-      ((window->size_hints.flags & PPosition) ||
-       (window->size_hints.flags & USPosition)))
+      ((window->size_hints.flags & META_SIZE_HINTS_PROGRAM_POSITION) ||
+       (window->size_hints.flags & META_SIZE_HINTS_USER_POSITION)))
     need_configure_notify = TRUE;
 
   /* If resizing, freeze commits - This is for Xwayland, and a no-op on Xorg */
@@ -2660,11 +2660,11 @@ meta_window_move_resize_request (MetaWindow  *window,
           window->type == META_WINDOW_MODAL_DIALOG ||
           window->type == META_WINDOW_SPLASHSCREEN)
         ; /* No position change for these */
-      else if ((window->size_hints.flags & PPosition) ||
-               /* USPosition is just stale if window is placed;
+      else if ((window->size_hints.flags & META_SIZE_HINTS_PROGRAM_POSITION) ||
+               /* USER_POSITION is just stale if window is placed;
                 * no --geometry involved here.
                 */
-               ((window->size_hints.flags & USPosition) &&
+               ((window->size_hints.flags & META_SIZE_HINTS_USER_POSITION) &&
                 !window->placed))
         allow_position_change = TRUE;
     }
@@ -2693,9 +2693,9 @@ meta_window_move_resize_request (MetaWindow  *window,
   else
     {
       meta_topic (META_DEBUG_GEOMETRY,
-		  "Not allowing position change for window %s PPosition 0x%lx USPosition 0x%lx type %u",
-		  window->desc, window->size_hints.flags & PPosition,
-		  window->size_hints.flags & USPosition,
+		  "Not allowing position change for window %s PROGRAM_POSITION 0x%lx USER_POSITION 0x%lx type %u",
+		  window->desc, window->size_hints.flags & META_SIZE_HINTS_PROGRAM_POSITION,
+		  window->size_hints.flags & META_SIZE_HINTS_USER_POSITION,
 		  window->type);
     }