Re: [Qemu-devel] [PATCH] tests: vm: auto_install OpenBSD

[Peter Maydell]

On 24 August 2018 at 15:43, Daniel P. Berrangé <address@hidden> wrote:
> On Fri, Aug 24, 2018 at 10:36:30AM -0400, Brad Smith wrote:
>> I very much appreciate the effort to bump up to 6.3 as I was going
>> to suggest doing that at some point. But bumping up to 6.3 at the
>> moment will fail with the configure script. We've switched from GCC 4.2
>> to Clang. The TLS check will fail with Clang's emulated TLS. We've
>> had a local patch for awhile to fix the test but I don't think it is
>> appropriate to upstream as is.
>>
>> Index: configure
>> --- configure.orig
>> +++ configure
>> @@ -1876,7 +1876,7 @@ static __thread int tls_var;
>>  int main(void) { return tls_var; }
>>  EOF
>> -if ! compile_prog "-Werror" "" ; then
>> +if ! compile_prog "-Werror" "-pthread" ; then
>>      error_exit "Your compiler does not support the __thread specifier for " 
>> \
>>       "Thread-Local Storage (TLS). Please upgrade to a version that does."
>>  fi
>
> Later on in the configure script there's a check for pthreads that
> sets $PTHREAD_LIB to the desired arg.
>
> Best is probably to move that check higher up, and then use $PTHREAD_LIB
> as the argument to the compile_prog call you show.

Is emulated TLS a sufficiently complete/performant TLS
implementation for our purposes?

(I think it would be better if OpenBSD just implemented real TLS
like every other host OS we support.)

thanks
-- PMM