[Bug c++/98130] [11 regression] placement new fails on webkit-gtk-2.28.4 since r11-4745-g58c9de46541ade79

["rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98130

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #4)
> That would mean:
> 
> --- gcc/testsuite/g++.dg/opt/pr98130.C.jj	2020-12-04 12:30:11.510988404 +0100
> +++ gcc/testsuite/g++.dg/opt/pr98130.C	2020-12-04 12:33:05.663028984 +0100
> @@ -0,0 +1,25 @@
> +// PR c++/98130
> +// { dg-do run { target c++11 } }
> +// { dg-options "-O2" }
> +
> +#include <new>
> +
> +typedef int *T;
> +
> +static unsigned char storage[sizeof (T)] alignas (T);
> +static T *p = (T *) storage;
> +
> +static inline __attribute__((__always_inline__)) void
> +foo (T value)
> +{
> +  new (p) T(value);
> +}
> +
> +int
> +main ()
> +{
> +  int a;
> +  foo (&a);
> +  if (!*p)
> +    __builtin_abort ();
> +}
> --- gcc/gimple.c.jj	2020-11-26 01:14:47.528081989 +0100
> +++ gcc/gimple.c	2020-12-04 12:34:44.865911907 +0100
> @@ -1514,11 +1514,12 @@ gimple_call_fnspec (const gcall *stmt)
>       such operator, then we can treat it as free.  */
>    if (fndecl
>        && DECL_IS_OPERATOR_DELETE_P (fndecl)
> +      && DECL_IS_REPLACEABLE_OPERATOR (fndecl)
>        && gimple_call_from_new_or_delete (stmt))
>      return ".co ";
>    /* Similarly operator new can be treated as malloc.  */
>    if (fndecl
> -      && DECL_IS_OPERATOR_NEW_P (fndecl)
> +      && DECL_IS_REPLACEABLE_OPERATOR_NEW_P (fndecl)
>        && gimple_call_from_new_or_delete (stmt))
>      return "mC";
>    return "";
> 
> but the testcase is miscompiled even with that change, and we don't really
> return ".co " nor "mC" on the testcase.

The fix works for me?  Note I think we don't need the extra check on
the delete case.