Re: [PATCH 7/8] Remove __after_morecore_hook

[DJ Delorie <dj@redhat.com>]

Siddhesh Poyarekar <siddhesh@sourceware.org> writes:
> Remove __after_morecore_hook from the API and finalize the symbol so
> that it can no longer be used in new applications.  Old applications
> using __after_morecore_hook will find that their hook is no longer
> called.

> diff --git a/malloc/hooks.c b/malloc/hooks.c
> index cc9ffc8b63..fa6b3f4c16 100644
> --- a/malloc/hooks.c
> +++ b/malloc/hooks.c
> @@ -78,6 +78,9 @@ compat_symbol (libc, __malloc_hook, __malloc_hook, GLIBC_2_0);
>  compat_symbol (libc, __realloc_hook, __realloc_hook, GLIBC_2_0);
>  compat_symbol (libc, __memalign_hook, __memalign_hook, GLIBC_2_0);
>  
> +void weak_variable (*__after_morecore_hook) (void) = NULL;
> +compat_symbol (libc, __after_morecore_hook, __after_morecore_hook, GLIBC_2_0);
> +

Ok.

> diff --git a/malloc/malloc.c b/malloc/malloc.c
> index 16ad933c66..51970105b5 100644
> --- a/malloc/malloc.c
> +++ b/malloc/malloc.c
> @@ -1988,16 +1988,6 @@ static void     malloc_consolidate (mstate);
>  
>  /* -------------- Early definitions for debugging hooks ---------------- */
>  
> -/* Define and initialize the hook variables.  These weak definitions must
> -   appear before any use of the variables in a function (arena.c uses one).  */
> -#ifndef weak_variable
> -/* In GNU libc we want the hook variables to be weak definitions to
> -   avoid a problem with Emacs.  */
> -# define weak_variable weak_function
> -#endif
> -
> -void weak_variable (*__after_morecore_hook) (void) = NULL;
> -

Ok.

> @@ -2622,14 +2612,7 @@ sysmalloc (INTERNAL_SIZE_T nb, mstate av)
>            LIBC_PROBE (memory_sbrk_more, 2, brk, size);
>          }
>  
> -      if (brk != (char *) (MORECORE_FAILURE))
> -        {
> -          /* Call the `morecore' hook if necessary.  */
> -          void (*hook) (void) = atomic_forced_read (__after_morecore_hook);
> -          if (__builtin_expect (hook != NULL, 0))
> -            (*hook)();
> -        }
> -      else
> +      if (brk == (char *) (MORECORE_FAILURE))

Ok.

> @@ -2768,13 +2751,6 @@ sysmalloc (INTERNAL_SIZE_T nb, mstate av)
>                        correction = 0;
>                        snd_brk = (char *) (MORECORE (0));
>                      }
> -                  else
> -                    {
> -                      /* Call the `morecore' hook if necessary.  */
> -                      void (*hook) (void) = atomic_forced_read (__after_morecore_hook);
> -                      if (__builtin_expect (hook != NULL, 0))
> -                        (*hook)();
> -                    }

Ok.

> @@ -2933,10 +2909,6 @@ systrim (size_t pad, mstate av)
>         */
>  
>        MORECORE (-extra);
> -      /* Call the `morecore' hook if necessary.  */
> -      void (*hook) (void) = atomic_forced_read (__after_morecore_hook);
> -      if (__builtin_expect (hook != NULL, 0))
> -        (*hook)();
>        new_brk = (char *) (MORECORE (0));

Ok.

> diff --git a/malloc/malloc.h b/malloc/malloc.h
> index 709fa454b5..d066a05d82 100644
> --- a/malloc/malloc.h
> +++ b/malloc/malloc.h
> @@ -164,10 +164,5 @@ extern void malloc_stats (void) __THROW;
>  /* Output information about state of allocator to stream FP.  */
>  extern int malloc_info (int __options, FILE *__fp) __THROW;
>  
> -/* Hooks for debugging and user-defined versions. */
> -extern void (*__MALLOC_HOOK_VOLATILE __after_morecore_hook) (void)
> -  __MALLOC_DEPRECATED;
> -
> -
>  __END_DECLS
>  #endif /* malloc.h */

Ok.

LGTM
Reviewed-by: DJ Delorie <dj@redhat.com>