[COMMITTED] malloc: Fix mallinfo deprecation declaration

[Adhemerval Zanella]

On 04/09/2020 14:02, Vaseeharan Vinayagamoorthy wrote:
> I am seeing these deprecated-declaration errors when compiling ggc-common.c.
> 
> /src/gcc/gcc/ggc-common.c:1018:62: error: 'mallinfo mallinfo()' is deprecated [-Werror=deprecated-declarations]
>  1018 |     fprintf (stderr," {heap %luk}", (unsigned long)(mallinfo().arena / 1024));
>       |                                                              ^
> In file included from /src/gcc/gcc/system.h:736,
>                  from src/gcc/gcc/ggc-common.c:25:
> /usr/include/malloc.h:118:24: note: declared here
>   118 | extern struct mallinfo mallinfo (void) __THROW __MALLOC_DEPRECATED;
> 
> This is breaking the build for these configurations:
> BUILD: aarch64-none-linux-gnu
> HOST: aarch64-none-linux-gnu
> TARGET: aarch64-none-linux-gnu
> 
> BUILD: arm-none-linux-gnueabihf
> HOST: arm-none-linux-gnueabihf
> TARGET: arm-none-linux-gnueabihf
> 
> Glibc is being bootstrapped in these configurations.

Yes, that the whole point of the deprecation patch and this was indeed
proposed by a gcc developer to fix a issue on gcc.  This is being discussed 
on gcc-patch thread [1] and the idea is if 'mallinfo2' is supported to use 
it instead of 'mallinfo'. Meanwhile I think the best option it to not use 
-Werror=deprecated-declarations.

[1] https://gcc.gnu.org/pipermail/gcc-patches/2020-September/553077.html

> 
> 
> 
> On 31/08/2020, 18:47, "Libc-alpha on behalf of Adhemerval Zanella via Libc-alpha" <libc-alpha-bounces@sourceware.org on behalf of libc-alpha@sourceware.org> wrote:
> 
>     It fixes the build issue below introduced by e3960d1c57e57 (Add
>     mallinfo2  function that support sizes >= 4GB).  It moves the
>     __MALLOC_DEPRECATED to the usual place for function attributes:
> 
>       In file included from ../include/malloc.h:3,
>                        from ../sysdeps/x86_64/multiarch/../../../test-skeleton.c:31,
>                        from ../sysdeps/x86_64/multiarch/test-multiarch.c:96:
>       ../malloc/malloc.h:118:1: error: empty declaration [-Werror]
>         118 | __MALLOC_DEPRECATED;
> 
>     It also adds the required deprecated warning suppression on the tests.
> 
>     Checked on x86_64-linux-gnu.
>     ---
>      malloc/malloc.h                 | 3 +--
>      malloc/tst-malloc-tcache-leak.c | 7 +++++++
>      malloc/tst-mxfast.c             | 7 +++++++
>      3 files changed, 15 insertions(+), 2 deletions(-)
> 
>     diff --git a/malloc/malloc.h b/malloc/malloc.h
>     index e25b33462a..b2371f7704 100644
>     --- a/malloc/malloc.h
>     +++ b/malloc/malloc.h
>     @@ -115,8 +115,7 @@ struct mallinfo2
>      };
> 
>      /* Returns a copy of the updated current mallinfo. */
>     -__MALLOC_DEPRECATED;
>     -extern struct mallinfo mallinfo (void) __THROW;
>     +extern struct mallinfo mallinfo (void) __THROW __MALLOC_DEPRECATED;
> 
>      /* Returns a copy of the updated current mallinfo. */
>      extern struct mallinfo2 mallinfo2 (void) __THROW;
>     diff --git a/malloc/tst-malloc-tcache-leak.c b/malloc/tst-malloc-tcache-leak.c
>     index f6f6023b5a..2a7a0646c5 100644
>     --- a/malloc/tst-malloc-tcache-leak.c
>     +++ b/malloc/tst-malloc-tcache-leak.c
>     @@ -29,6 +29,7 @@
>      #include <malloc.h>
>      #include <pthread.h>
>      #include <assert.h>
>     +#include <libc-diag.h>
> 
>      #include <support/check.h>
>      #include <support/support.h>
>     @@ -72,6 +73,10 @@ do_test (void)
>           pthread_t required to run the test.  */
>        thread = (pthread_t *) xcalloc (1, sizeof (pthread_t));
> 
>     +  /* The test below covers the deprecated mallinfo function.  */
>     +  DIAG_PUSH_NEEDS_COMMENT;
>     +  DIAG_IGNORE_NEEDS_COMMENT (4.9, "-Wdeprecated-declarations");
>     +
>        info_before = mallinfo ();
> 
>        assert (info_before.uordblks != 0);
>     @@ -104,6 +109,8 @@ do_test (void)
>        if (info_after.uordblks > (info_before.uordblks + threads))
>          FAIL_EXIT1 ("Memory usage after threads is too high.\n");
> 
>     +  DIAG_POP_NEEDS_COMMENT;
>     +
>        /* Did not detect excessive memory usage.  */
>        free (thread);
>        exit (0);
>     diff --git a/malloc/tst-mxfast.c b/malloc/tst-mxfast.c
>     index 57b4a0a8dc..8afee0f9d5 100644
>     --- a/malloc/tst-mxfast.c
>     +++ b/malloc/tst-mxfast.c
>     @@ -21,6 +21,7 @@
>         the fast bins.  */
> 
>      #include <malloc.h>
>     +#include <libc-diag.h>
>      #include <support/check.h>
> 
>      int
>     @@ -36,8 +37,14 @@ do_test (void)
>        p2 = malloc (512);
>        free (p1);
> 
>     +  /* The test below covers the deprecated mallinfo function.  */
>     +  DIAG_PUSH_NEEDS_COMMENT;
>     +  DIAG_IGNORE_NEEDS_COMMENT (4.9, "-Wdeprecated-declarations");
>     +
>        m = mallinfo ();
> 
>     +  DIAG_POP_NEEDS_COMMENT;
>     +
>        /* This will fail if there are any blocks in the fastbins.  */
>        TEST_COMPARE (m.smblks, 0);
> 
>     -- 
>     2.25.1
> 
>