Re: [PATCH] __builtin_apply / -fdefer-pop bug (ObjC fix!)

[Richard Henderson <rth@cygnus.com>]

On Wed, Jul 26, 2000 at 04:36:07PM -0400, Jason McMullan wrote:
> 	When compiled with -fdefer-pop (without the following
> patch) GCC neglects to set the stack pointer appropriately
> after the memcpy() call (to move the stack arguments), and
> the called function (that __builtin_apply() was trying to call)
> is sent a bogus stack pointer.

You didn't point at a test case, which would have been helpful.
Nor did you work against current gcc sources, which have changed.

However, the solution seems reasonable.  I've applied the following.


r~


2000-07-31  Jason McMullan  <jmcmullan@linuxcare.com>

        * builtins.c (expand_builtin_apply): Don't defer pop during
        argument setup.

Index: builtins.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/builtins.c,v
retrieving revision 1.51
diff -c -p -d -r1.51 builtins.c
*** builtins.c	2000/07/03 18:28:33	1.51
--- builtins.c	2000/07/31 16:34:43
*************** expand_builtin_apply (function, argument
*** 885,892 ****
    /* Perform postincrements before actually calling the function.  */
    emit_queue ();
  
!   /* Push a new argument block and copy the arguments.  */
    do_pending_stack_adjust ();
  
    /* Save the stack with nonlocal if available */
  #ifdef HAVE_save_stack_nonlocal
--- 885,895 ----
    /* Perform postincrements before actually calling the function.  */
    emit_queue ();
  
!   /* Push a new argument block and copy the arguments.  Do not allow
!      the (potential) memcpy call below to interfere with our stack
!      manipulations.  */
    do_pending_stack_adjust ();
+   NO_DEFER_POP;
  
    /* Save the stack with nonlocal if available */
  #ifdef HAVE_save_stack_nonlocal
*************** expand_builtin_apply (function, argument
*** 1025,1030 ****
--- 1028,1035 ----
    else
  #endif
      emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
+ 
+   OK_DEFER_POP;
  
    /* Return the address of the result block.  */
    return copy_addr_to_reg (XEXP (result, 0));