[Info-vax] gnulib test-fmal-ieee failure help needed.

[John E. Malmberg]

On 7/22/2017 10:52 PM, John E. Malmberg wrote:
> On 7/22/2017 10:09 PM, Craig A. Berry wrote:
>> On 7/22/17 8:54 PM, John E. Malmberg wrote:
>>> The gnulib test-fmal-ieee is failing for the gnulib provided fmal 
>>> routine.
>>>
>>> Actually a lot of the IEEE tests are failing.
>>>
>>> My compiler command line on OpenVMS 8.4 is:
>>>
>>> CC/STANDARD=(RELAXED)/ACCEPT=(NOVAXC,RESTR,C99)-
>>>    /LIST/SHOW=(EXPAN,INCLU)/NAMES=(AS_IS,SHORT)-
>>>    /MAIN=POSIX_EXIT-
>>>    /FLOAT=IEEE/IEEE_MODE=DENORM_RESULTS-
>>>    /NESTED=NONE-
>>>    /PREFIX=EXCEPT=(STRTOIMAX,STRTOUMAX,ISWBLANK,ISBLANK)-
>>>    /WARN=(DISABLE=QUESTCOMPARE)-
>>>    /DEBUG/NOOPTIMIZE/DEB=ALL/NOOPT-
>>>    /DEF=-(HAVE_CONFIG_H,EXEEXT="",EXEEXT="",NO_XMALLOC,EXEEXT="",-
>>>           GNULIB_STRICT_CHECKING=1,_POSIX_EXIT,_USE_STD_STAT,-
>>>        _  _USE_STD_IOSTREAM)-
>>>     /INC=(./,../)/OBJECT=SYS$DISK:[]fmal.o SYS$DISK:[]fmal.c
>>>
>>> The floating variables involved are declared double.
>>>
>>> The input to the failed call is:
>>>
>>>   fmal(Infinity, 2.0L, -Infinity) and the result is expected to be NaN.
>>>
>>> Is there some other compile settings that I should be using to be 
>>> more compatible with GNULIB's expectations for IEEE math?
>>
>> fmal is for long doubles, so passing doubles to it is unlikely to work.
>> For example, you probably want LDBL_INFINITY instead of Infinity.
>> Possibly related is that none of the IEEE test macros (isnan, isinf,
>> etc.) in math.h on VMS works for floats or long doubles -- they only
>> work for doubles. Which is a bug. We have some workarounds in Perl for
>> some of it.
> 
> Your right, the gnulib fmal code is long doubles, not doubles.
> 
> VMS has a number of the declarations that should be in math.h in fp.h.
> 
> In this case INFINITY is defined as decc$gt_gbl_infinity by fp.h and is 
> reported as Infinity in the VMS debugger.

The test-fmal1 fails in the same way as test-fmal-ieee.

The test-malm2 fails when fma returns what the debugger says is Infinity 
and the test was expecting "-Infinity".

DBG> eval result
Infinity
DBG> eval -result
-Infinity

These results are showing up while am running the failed tests in debug 
to get more information.  So as soon as I exit one failed test, the 
script moves on to the next.  I am not sure how many more tests are 
going to run in this pass.

Regards,
  -John
  wb8tyw at qsl.net_work