rs6000.c (function_arg_pass_by_reference): Don't pass zero-size arrays by reference.

2003-09-23  Geoffrey Keating  <geoffk@apple.com>

	* config/rs6000/rs6000.c (function_arg_pass_by_reference): Don't
	pass zero-size arrays by reference.
	(rs6000_va_arg): Likewise.

2003-09-23  Geoffrey Keating  <geoffk@apple.com>

	* gcc.dg/darwin-abi-1.c: New file.

From-SVN: r71698

gcc/ChangeLog

+2003-09-23  Geoffrey Keating  <geoffk@apple.com>
+
+	* config/rs6000/rs6000.c (function_arg_pass_by_reference): Don't
+	pass zero-size arrays by reference.
+	(rs6000_va_arg): Likewise.
+
 2003-09-23  Nathanael Nerode  <neroden@gcc.gnu.org>
 
 	* config.gcc: Set use_fixproto=no in each specific *-gnu*

gcc/config/rs6000/rs6000.c

@@ -3977,7 +3977,7 @@ function_arg_pass_by_reference (CUMULATIVE_ARGS *cum ATTRIBUTE_UNUSED,
 
       return 1;
     }
-  return type && int_size_in_bytes (type) <= 0;
+  return type && int_size_in_bytes (type) < 0;
 }
 
 /* Perform any needed actions needed for a function that is receiving a
@@ -4206,7 +4206,7 @@ rs6000_va_arg (tree valist, tree type)
   if (DEFAULT_ABI != ABI_V4)
     {
       /* Variable sized types are passed by reference.  */
-      if (int_size_in_bytes (type) <= 0)
+      if (int_size_in_bytes (type) < 0)
 	{
 	  u = build_pointer_type (type);
 

gcc/testsuite/ChangeLog

+2003-09-23  Geoffrey Keating  <geoffk@apple.com>
+
+	* gcc.dg/darwin-abi-1.c: New file.
+
 2003-09-21  Andrew Pinski  <pinskia@physics.uc.edu>
 
 	PR target/12281

gcc/testsuite/gcc.dg/darwin-abi-1.c

+/* { dg-do compile { target powerpc*-*-darwin* } } */
+/* { dg-options "-O" } */
+/* { dg-final { scan-assembler "li r3,12345\n\tbl " } } */
+
+/* Check that zero-size structures don't affect parameter passing.  */
+
+struct empty { };
+extern void foo (struct empty e, int a);
+void bar (void) {
+  struct empty e;
+  foo (e, 12345);
+}