diff --git a/ui_windows.h b/ui_windows.h
index f2bfd4bd..8bd8c8c4 100644
--- a/ui_windows.h
+++ b/ui_windows.h
@@ -28,8 +28,10 @@ struct uiWindowsNewControlParams {
 	BOOL (*onWM_COMMAND)(uiControl *c, WORD code, LRESULT *lResult);
 	// TODO set idFrom to 0?
 	BOOL (*onWM_NOTIFY)(uiControl *c, NMHDR *nm, LRESULT *lResult);
-	// This is called in WM_DESTROY.
-	void (*onWM_DESTROY)(uiControl *c);
+
+	// This is called when the widget is ready to be destroyed.
+	void (*onDestroy)(void *data);
+	void *onDestroyData;
 };
 void uiWindowsNewControl(uiControl *c, uiWindowsNewControlParams *p);
 
diff --git a/windows/button.c b/windows/button.c
index 42a5f0e7..0f0b2d93 100644
--- a/windows/button.c
+++ b/windows/button.c
@@ -24,9 +24,9 @@ static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 	return FALSE;
 }
 
-static void onWM_DESTROY(uiControl *c)
+static void onDestroy(void *data)
 {
-	struct button *b = (struct button *) c;
+	struct button *b = (struct button *) data;
 
 	uiFree(b);
 }
@@ -95,7 +95,8 @@ uiButton *uiNewButton(const char *text)
 	p.useStandardControlFont = TRUE;
 	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
-	p.onWM_DESTROY = onWM_DESTROY;
+	p.onDestroy = onDestroy;
+	p.onDestroyData = b;
 	uiWindowsNewControl(uiControl(b), &p);
 	uiFree(wtext);
 
diff --git a/windows/checkbox.c b/windows/checkbox.c
index 08c31f0e..5d39622a 100644
--- a/windows/checkbox.c
+++ b/windows/checkbox.c
@@ -32,9 +32,9 @@ static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 	return FALSE;
 }
 
-static void onWM_DESTROY(uiControl *cc)
+static void onDestroy(void *data)
 {
-	struct checkbox *c = (struct checkbox *) cc;
+	struct checkbox *c = (struct checkbox *) data;
 
 	uiFree(c);
 }
@@ -110,7 +110,8 @@ uiCheckbox *uiNewCheckbox(const char *text)
 	p.useStandardControlFont = TRUE;
 	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
-	p.onWM_DESTROY = onWM_DESTROY;
+	p.onDestroy = onDestroy;
+	p.onDestroyData = c;
 	uiWindowsNewControl(uiControl(c), &p);
 	uiFree(wtext);
 
diff --git a/windows/entry.c b/windows/entry.c
index 2a3630ee..2aa066a2 100644
--- a/windows/entry.c
+++ b/windows/entry.c
@@ -16,9 +16,9 @@ static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 	return FALSE;
 }
 
-static void onWM_DESTROY(uiControl *c)
+static void onDestroy(void *data)
 {
-	struct entry *e = (struct entry *) c;
+	struct entry *e = (struct entry *) data;
 
 	uiFree(e);
 }
@@ -58,7 +58,8 @@ uiEntry *uiNewEntry(void)
 	p.useStandardControlFont = TRUE;
 	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
-	p.onWM_DESTROY = onWM_DESTROY;
+	p.onDestroy = onDestroy;
+	p.onDestroyData = e;
 	uiWindowsNewControl(uiControl(e), &p);
 
 	e->hwnd = HWND(e);
diff --git a/windows/label.c b/windows/label.c
index 066b2271..916d0ca8 100644
--- a/windows/label.c
+++ b/windows/label.c
@@ -16,9 +16,9 @@ static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 	return FALSE;
 }
 
-static void onWM_DESTROY(uiControl *c)
+static void onDestroy(void *data)
 {
-	struct label *l = (struct label *) c;
+	struct label *l = (struct label *) data;
 
 	uiFree(l);
 }
@@ -63,7 +63,8 @@ uiLabel *uiNewLabel(const char *text)
 	p.useStandardControlFont = TRUE;
 	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
-	p.onWM_DESTROY = onWM_DESTROY;
+	p.onDestroy = onDestroy;
+	p.onDestroyData = l;
 	uiWindowsNewControl(uiControl(l), &p);
 	uiFree(wtext);
 
diff --git a/windows/newcontrol.c b/windows/newcontrol.c
index 059a34db..4c4d89da 100644
--- a/windows/newcontrol.c
+++ b/windows/newcontrol.c
@@ -7,7 +7,8 @@ struct singleHWND {
 	HWND hwnd;
 	BOOL (*onWM_COMMAND)(uiControl *, WORD, LRESULT *);
 	BOOL (*onWM_NOTIFY)(uiControl *, NMHDR *, LRESULT *);
-	void (*onWM_DESTROY)(uiControl *);
+	void (*onDestroy)(void *);
+	void *onDestroyData;
 	uiParent *parent;
 	BOOL userHid;
 	BOOL containerHid;
@@ -165,7 +166,7 @@ static LRESULT CALLBACK singleSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam,
 	case WM_DESTROY:
 		if (!s->canDestroy)
 			complain("trying to destroy control with singleWidget at %p before uiControlDestroy()", s);
-		(*(s->onWM_DESTROY))(c);
+		(*(s->onDestroy))(s->onDestroyData);
 		uiFree(s);
 		break;
 	case WM_NCDESTROY:
@@ -192,7 +193,9 @@ void uiWindowsNewControl(uiControl *c, uiWindowsNewControlParams *p)
 		logLastError("error creating control in uiWindowsNewControl()");
 	s->onWM_COMMAND = p->onWM_COMMAND;
 	s->onWM_NOTIFY = p->onWM_NOTIFY;
-	s->onWM_DESTROY = p->onWM_DESTROY;
+
+	s->onDestroy = p->onDestroy;
+	s->onDestroyData = p->onDestroyData;
 
 	c->Destroy = singleDestroy;
 	c->Handle = singleHandle;
diff --git a/windows/tab.c b/windows/tab.c
index 39e52e40..5cb1619d 100644
--- a/windows/tab.c
+++ b/windows/tab.c
@@ -45,9 +45,9 @@ static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 	return FALSE;
 }
 
-static void onWM_DESTROY(uiControl *c)
+static void onDestroy(void *data)
 {
-	struct tab *t = (struct tab *) c;
+	struct tab *t = (struct tab *) data;
 	uintmax_t i;
 
 	for (i = 0; i < t->len; i++)
@@ -194,7 +194,8 @@ uiTab *uiNewTab(void)
 	p.useStandardControlFont = TRUE;
 	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
-	p.onWM_DESTROY = onWM_DESTROY;
+	p.onDestroy = onDestroy;
+	p.onDestroyData = t;
 	uiWindowsNewControl(uiControl(t), &p);
 
 	t->hwnd = HWND(t);
diff --git a/windows/uipriv_windows.h b/windows/uipriv_windows.h
index 929d0e52..1165a865 100644
--- a/windows/uipriv_windows.h
+++ b/windows/uipriv_windows.h
@@ -34,6 +34,7 @@ enum {
 	msgCOMMAND = WM_APP + 0x40,		// start offset just to be safe
 	msgNOTIFY,
 	msgUpdateChild,		// fake because Windows seems to SWP_NOSIZE MoveWindow()s and SetWindowPos()s that don't change the window size (even if SWP_NOSIZE isn't specified)
+	msgCanDestroyNow,
 };
 
 #define HWND(c) ((HWND) uiControlHandle(uiControl(c)))