--- tk8.5.15-orig/unix/Makefile.in	2014-01-25 08:57:45.626713122 +0800
+++ tk8.5.15/unix/Makefile.in	2014-01-25 08:59:35.315341825 +0800
@@ -995,7 +995,8 @@
 	$(CC) -c $(CC_SWITCHES) $(GENERIC_DIR)/tkVisual.c
 
 tkWindow.o: $(GENERIC_DIR)/tkWindow.c
-	$(CC) -c $(CC_SWITCHES) $(GENERIC_DIR)/tkWindow.c
+	$(CC) -c $(CC_SWITCHES) -DTK_LIBRARY=\"${TK_LIBRARY}\" \
+	    $(GENERIC_DIR)/tkWindow.c
 
 tkButton.o: $(GENERIC_DIR)/tkButton.c
 	$(CC) -c $(CC_SWITCHES) $(GENERIC_DIR)/tkButton.c
--- tk8.5.15-orig/generic/tkWindow.c	2014-01-25 10:10:03.964476436 +0800
+++ tk8.5.15/generic/tkWindow.c	2014-01-25 10:08:06.020950933 +0800
@@ -983,6 +983,7 @@
 
     Tcl_SetVar(interp, "tk_patchLevel", TK_PATCH_LEVEL, TCL_GLOBAL_ONLY);
     Tcl_SetVar(interp, "tk_version",    TK_VERSION,     TCL_GLOBAL_ONLY);
+    Tcl_SetVar(interp, "tk_library",    TK_LIBRARY,     TCL_GLOBAL_ONLY);
 
     tsdPtr->numMainWindows++;
     return tkwin;