Re: [PATCH v6] aarch64: Add split-stack support

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

On 13/02/2018 13:13, Szabolcs Nagy wrote:
> On 07/02/18 18:07, Adhemerval Zanella wrote:
>  5. The TCB support on GLIBC is meant to be included in version 2.28.
>>
> ...
>> +/* -fsplit-stack uses a TCB field available on glibc-2.27.  GLIBC also
>> +   exports symbol, __tcb_private_ss, to signal it has the field available
>> +   on TCB bloc.  This aims to prevent binaries linked against newer
>> +   GLIBC to run on non-supported ones.  */
> 
> 
> i suspect this needs to be updated since the glibc patch
> is not committed yet.
> 
> (i'll review the glibc patch, if it looks ok then it can
> be committed after the gcc side is accepted.)

I fixed the commit message locally, thanks for checking on this.

> 
>> +
>> +static bool
>> +aarch64_supports_split_stack (bool report ATTRIBUTE_UNUSED,
>> +                  struct gcc_options *opts ATTRIBUTE_UNUSED)
>> +{
>> +#ifndef TARGET_GLIBC_MAJOR
>> +#define TARGET_GLIBC_MAJOR 0
>> +#endif
>> +#ifndef TARGET_GLIBC_MINOR
>> +#define TARGET_GLIBC_MINOR 0
>> +#endif
>> +  /* Note: Can't test DEFAULT_ABI here, it isn't set until later.  */
>> +  if (TARGET_GLIBC_MAJOR * 1000 + TARGET_GLIBC_MINOR >= 2026)
>> +    return true;
>> +
>> +  if (report)
>> +    error ("%<-fsplit-stack%> currently only supported on AArch64 GNU/Linux with glibc-2.27 or later");
>> +  return false;
>> +}
>> +
>> +#undef TARGET_SUPPORTS_SPLIT_STACK
>> +#define TARGET_SUPPORTS_SPLIT_STACK aarch64_supports_split_stack
>> +