[PATCH] Define __PTHREAD_MUTEX_HAVE_PREV only if undefined [BZ #22298]

[Andreas Schwab]

On Okt 16 2017, Adhemerval Zanella <adhemerval.zanella@linaro.org> wrote:

> diff --git a/sysdeps/nptl/bits/thread-shared-types.h b/sysdeps/nptl/bits/thread-shared-types.h
> index 68b82b6..5dfe01e 100644
> --- a/sysdeps/nptl/bits/thread-shared-types.h
> +++ b/sysdeps/nptl/bits/thread-shared-types.h
> @@ -58,8 +58,7 @@
>  #include <bits/pthreadtypes-arch.h>
>  
>  /* Common definition of pthread_mutex_t. */
> -
> -#if __WORDSIZE == 64
> +#if __PTHREAD_MUTEX_HAVE_PREV
>  typedef struct __pthread_internal_list
>  {
>    struct __pthread_internal_list *__prev;
> @@ -74,7 +73,7 @@ typedef struct __pthread_internal_slist
>  
>  /* Lock elision support.  */
>  #if __PTHREAD_MUTEX_LOCK_ELISION
> -# if __WORDSIZE == 64
> +# if __PTHREAD_MUTEX_HAVE_PREV
>  #  define __PTHREAD_SPINS_DATA	\
>    short __spins;		\
>    short __elision
> @@ -101,17 +100,16 @@ struct __pthread_mutex_s
>    int __lock __LOCK_ALIGNMENT;
>    unsigned int __count;
>    int __owner;
> -#if __WORDSIZE == 64
> +#if __PTHREAD_MUTEX_HAVE_PREV
>    unsigned int __nusers;
>  #endif

The name doesn't really fit here.  There is nothing matching prev in
__nusers or __PTHREAD_SPINS_DATA.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."