makefiles: Always create dependencies from the top-level directory.

Make.rules.in

@@ -20,13 +20,6 @@ OBJS = $(C_SRCS:.c=.o) $(BISON_SRCS:.y=.tab.o) $(LEX_SRCS:.l=.yy.o) $(OBJC_SRCS:
 
 ALLCROSSCFLAGS = $(CPPFLAGS) $(CFLAGS)
 
-# Rules for dependencies
-
-depend: dummy
-	$(MAKEDEP) -M .
-
-.PHONY: depend
-
 # Rules for cleaning
 
 clean::

tools/makedep.c

@@ -1944,6 +1944,7 @@ static struct strarray output_sources(void)
         output( "\t$(RM)" );
         output_filenames( clean_files );
         output( "\n" );
+        strarray_add( &phony_targets, "clean" );
     }
 
     if (subdirs.count)
@@ -1953,6 +1954,13 @@ static struct strarray output_sources(void)
         output( "\t$(MKDIR_P) -m 755 $@\n" );
     }
 
+    if (top_obj_dir)
+    {
+        output( "depend:\n" );
+        output( "\t@cd %s && $(MAKE) %s/depend\n", top_obj_dir, base_dir );
+        strarray_add( &phony_targets, "depend" );
+    }
+
     if (phony_targets.count)
     {
         output( ".PHONY:" );