------- Additional Comments From pinskia at gcc dot gnu dot org 2005-03-10
17:30 -------
(In reply to comment #10)
> I think we should produce an empty CONSTRUCTOR (which I am testing right now).
That did not fix it, we still get code generated for the "empty" struct:
;; D.1594 = {}
(nil)
;; foo (D.1594) [tail call]
(insn 10 8 11 (set (mem:QI (reg/f:SI 56 virtual-outgoing-args) [0 S1 A32])
(reg:QI 58 [ D.1594 ])) -1 (nil)
(nil))
(call_insn 11 10 0 (call (mem:QI (symbol_ref:SI ("_Z3foo1X") [flags 0x41]
<function_decl 0x41e9ea6c
foo>) [0 S1 A8])
(const_int 4 [0x4])) -1 (nil)
(nil)
(nil))
But on PPC we get:
;; D.1588 = {}
(nil)
;; foo (D.1588) [tail call]
(insn 10 8 11 0 (set (reg:QI 3 r3)
(reg:QI 118 [ D.1588 ])) -1 (nil)
(nil))
(call_insn/j 11 10 12 0 (parallel [
(call (mem:SI (symbol_ref:SI ("_Z3foo1X") [flags 0x41]
<function_decl 0x41d9f984 foo>) [0 S4
A8])
(const_int 32 [0x20]))
(use (const_int 0 [0x0]))
(use (reg:SI 119))
(return)
]) -1 (nil)
(nil)
(expr_list:REG_DEP_TRUE (use (reg:QI 3 r3))
(nil)))
See the difference is that we pass on ppc via a register but on x86 we pass via
the stack. I don't know a
way to fix this with a front-end change.
--
What |Removed |Added
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Component|c++ |middle-end
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20408
