Re: [PATCH v3] nptl: Deallocate the thread stack on setup failure (BZ #19511)

[Florian Weimer <fweimer@redhat.com>]

* Joseph Myers:

> On Wed, 2 Jun 2021, Andreas Schwab wrote:
>
>> On Jun 02 2021, Adhemerval Zanella wrote:
>> 
>> > I don't have a strong preference here, maybe use a 'bool' then?
>> 
>> bool has architecture dependent size.
>
> bool is one byte for all configurations supported by glibc (the only 
> configuration supported by GCC for which it isn't is powerpc-darwin).  
> Although I don't see any likely reason for glibc code to depend on it 
> being one byte.

However, one reason not to use bool in internal code is that our own
atomics do not support one-byte types on all architectures.

For example this definition in sysdeps/powerpc/atomic-machine.h:

#define atomic_exchange_acq(mem, value) \
  ({                                                                          \
    __typeof (*(mem)) __result;                                               \
    if (sizeof (*mem) == 4)                                                   \
      __result = __arch_atomic_exchange_32_acq (mem, value);                  \
    else if (sizeof (*mem) == 8)                                              \
      __result = __arch_atomic_exchange_64_acq (mem, value);                  \
    else                                                                      \
       abort ();                                                              \
    __result;                                                                 \
  })

Thanks,
Florian