Using weak symbols rather than __attribute__((constructor)) preserves the
linking order as on other platforms.
--- a/src/Vendor.c.orig	2023-05-13 04:08:46
+++ b/src/Vendor.c	2024-05-23 01:25:07
@@ -112,21 +112,12 @@
 void XawVendorStructureNotifyHandler(Widget, XtPointer, XEvent*, Boolean*);
 
 
-#if defined(__CYGWIN__) || defined(__MINGW32__) || defined(__APPLE__)
+#if defined(__CYGWIN__) || defined(__MINGW32__)
 /* to fix the EditRes problem because of wrong linker semantics */
 extern WidgetClass vendorShellWidgetClass; /* from Xt/Vendor.c */
 extern VendorShellClassRec _XawVendorShellClassRec;
 void _XawFixupVendorShell(void);
 
-#if defined(__APPLE__)
-__attribute__((constructor))
-static void __VendorShellHack(void)
-{
-    vendorShellWidgetClass = (WidgetClass)(&_XawVendorShellClassRec);
-    _XawFixupVendorShell();
-}
-#endif
-
 #if defined(__CYGWIN__) || defined(__MINGW32__)
 int __stdcall DllMain(unsigned long, unsigned long, void *);
 
@@ -162,6 +153,9 @@
 #endif
 
 #define SuperClass (&wmShellClassRec)
+#if defined(__APPLE__)
+__attribute__((weak))
+#endif
 externaldef(vendorshellclassrec) VendorShellClassRec vendorShellClassRec = {
   {
     /* superclass	  */	(WidgetClass)SuperClass,
@@ -223,10 +217,11 @@
   }
 };
 
-#if !defined(__APPLE__)
+#if defined(__APPLE__)
+__attribute__((weak))
+#endif
 externaldef(vendorshellwidgetclass) WidgetClass vendorShellWidgetClass =
 	(WidgetClass) (&vendorShellClassRec);
-#endif
 
 #ifdef XAW_INTERNATIONALIZATION
 /***************************************************************************
@@ -470,7 +465,7 @@
 }
 #endif
 
-#if defined(__CYGWIN__) || defined(__MINGW32__) || defined(__APPLE__)
+#if defined(__CYGWIN__) || defined(__MINGW32__)
 /* shared libraries on these platforms have the wrong semantics */
 /* symbols do not get resolved external to the shared library */
 void