malloc: Deprecate more hook-related functionality
Commit Message
__morecore, __after_morecore_hook and __after_morecore_hook had not
been deprecated in commit 7d17596c198f11fa85cbcf9587443f262e63b616
("Mark malloc hook variables as deprecated"), probably by accident.
Tested on i686-linux-gnu.
---
NEWS | 7 +++++++
malloc/malloc.h | 7 ++++---
2 files changed, 11 insertions(+), 3 deletions(-)
Comments
On 7/10/20 8:56 AM, Florian Weimer via Libc-alpha wrote:
OK for 2.32 with commit message fixed.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
> __morecore, __after_morecore_hook and __after_morecore_hook had not
Suggest:
__morecore, __after_morecore_hook, and __default_morecore had not ...
> been deprecated in commit 7d17596c198f11fa85cbcf9587443f262e63b616
> ("Mark malloc hook variables as deprecated"), probably by accident.
In my original patch to remove the malloc hooks:
https://sourceware.org/pipermail/libc-alpha/2018-June/095230.html
I note the following:
~~~
The functionality which is no longer supported is that provided by
__morecore, and __after_morecore_hook. The morecore related hooking is
entirely removed, and __default_morecore is always called with no
interposition possible (now named __glibc_morecore).
...
__morecore@GLIBC_2.2.5 (unused)
__default_morecore@GLIBC_2.2.5 (default)
__after_morecore_hook@GLIBC_2.2.5 (unused)
~~~
Your deprecation matches my expectations for additional functions
which would need deprecation, and matches my comments in the 2018 patch.
I appreciate your help here moving this interface towards removal.
> Tested on i686-linux-gnu.
>
> ---
> NEWS | 7 +++++++
> malloc/malloc.h | 7 ++++---
> 2 files changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/NEWS b/NEWS
> index 0b25b4fde9..8fb1dac36d 100644
> --- a/NEWS
> +++ b/NEWS
> @@ -131,6 +131,13 @@ Deprecated and removed features, and other changes affecting compatibility:
> storing RPC keys only supported the obsolete and insecure AUTH_DES
> flavor of secure RPC.)
>
> +* The __morecore and __after_morecore_hook malloc hooks and the default
> + implementation __default_morecore have been deprecated. Applications
> + should use malloc interposition to change malloc behavior, and mmap to
> + allocate anonymous memory. A future version of glibc may require that
> + applications which use the malloc hooks must preload a special shared
> + object, to enable the hooks.
OK.
> +
> Changes to build and runtime requirements:
>
> * powerpc64le requires GCC 7.4 or newer. This is required for supporting
> diff --git a/malloc/malloc.h b/malloc/malloc.h
> index a6903fdd54..e0e91a9331 100644
> --- a/malloc/malloc.h
> +++ b/malloc/malloc.h
> @@ -75,11 +75,11 @@ extern void *pvalloc (size_t __size) __THROW __attribute_malloc__ __wur;
>
> /* Underlying allocation function; successive calls should return
> contiguous pieces of memory. */
> -extern void *(*__morecore) (ptrdiff_t __size);
> +extern void *(*__morecore) (ptrdiff_t __size) __MALLOC_DEPRECATED;
OK.
>
> /* Default value of `__morecore'. */
> extern void *__default_morecore (ptrdiff_t __size)
> -__THROW __attribute_malloc__;
> +__THROW __attribute_malloc__ __MALLOC_DEPRECATED;
OK.
>
> /* SVID2/XPG mallinfo structure */
>
> @@ -156,7 +156,8 @@ extern void *(*__MALLOC_HOOK_VOLATILE __memalign_hook)(size_t __alignment,
> size_t __size,
> const void *)
> __MALLOC_DEPRECATED;
> -extern void (*__MALLOC_HOOK_VOLATILE __after_morecore_hook) (void);
> +extern void (*__MALLOC_HOOK_VOLATILE __after_morecore_hook) (void)
> + __MALLOC_DEPRECATED;
OK.
>
>
> __END_DECLS
>
@@ -131,6 +131,13 @@ Deprecated and removed features, and other changes affecting compatibility:
storing RPC keys only supported the obsolete and insecure AUTH_DES
flavor of secure RPC.)
+* The __morecore and __after_morecore_hook malloc hooks and the default
+ implementation __default_morecore have been deprecated. Applications
+ should use malloc interposition to change malloc behavior, and mmap to
+ allocate anonymous memory. A future version of glibc may require that
+ applications which use the malloc hooks must preload a special shared
+ object, to enable the hooks.
+
Changes to build and runtime requirements:
* powerpc64le requires GCC 7.4 or newer. This is required for supporting
@@ -75,11 +75,11 @@ extern void *pvalloc (size_t __size) __THROW __attribute_malloc__ __wur;
/* Underlying allocation function; successive calls should return
contiguous pieces of memory. */
-extern void *(*__morecore) (ptrdiff_t __size);
+extern void *(*__morecore) (ptrdiff_t __size) __MALLOC_DEPRECATED;
/* Default value of `__morecore'. */
extern void *__default_morecore (ptrdiff_t __size)
-__THROW __attribute_malloc__;
+__THROW __attribute_malloc__ __MALLOC_DEPRECATED;
/* SVID2/XPG mallinfo structure */
@@ -156,7 +156,8 @@ extern void *(*__MALLOC_HOOK_VOLATILE __memalign_hook)(size_t __alignment,
size_t __size,
const void *)
__MALLOC_DEPRECATED;
-extern void (*__MALLOC_HOOK_VOLATILE __after_morecore_hook) (void);
+extern void (*__MALLOC_HOOK_VOLATILE __after_morecore_hook) (void)
+ __MALLOC_DEPRECATED;
__END_DECLS