[Bug libstdc++/98384] [11 Regression] new test case 20_util/to_chars/long_double.cc in r11-6249 fails on powerpc64 BE

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98384

--- Comment #6 from Patrick Palka <ppalka at gcc dot gnu.org> ---
(In reply to Iain Sandoe from comment #4)
> (In reply to Patrick Palka from comment #3)
> > Candidate patch:
> > https://gcc.gnu.org/pipermail/gcc-patches/2021-January/563000.html
> 
> thanks!
> 
> On Darwin, the test case now builds (checked on a 32b host [powerpc] with a
> 64b multilib) and a 64b (x86_64) host.  The 32b multilib xfails the execute
> (as expected w/out int128 support)
> 
> On both powerpc (64b multilib) and x86_64:
> 
> test01 fails with : 
> src-local/gcc-master/libstdc++-v3/testsuite/20_util/to_chars/long_double.cc:
> 136: void test01(): Assertion '!strcmp(to_chars_buffer,
> printf_buffer+strlen("0x"))' failed.
> 
> (not analysed why yet).

Thanks for testing!  Hmm, that execute failure is surprising.  I wonder just
how much we're diverging from the output of printf here.  If possible, could
you let me know the value of the locals 'to_chars_buffer', 'printf_buffer',
'precision' and 'testcase' (ideally in hex form) at the point of the assertion
failure?