new libstdc++-v3 decimal failures

[Janis Johnson]

On Tue, 2009-10-06 at 09:10 -0700, Janis Johnson wrote:
> On Tue, 2009-10-06 at 09:04 -0400, Jack Howarth wrote:
> > Janis,
> >    We are seeing failures of the new decimal testcases on x86_64-apple-darwin10
> > which you committed into the libstdc++-v3 testsuite...
> > 
> > FAIL: decimal/binary-arith.cc (test for excess errors)
> > WARNING: decimal/binary-arith.cc compilation failed to produce executable
> <lots more failures>
> > 
> > Are these tests entirely glibc-centric and shouldn't they be disabled for
> > darwin?
> 
> Each test contains
> 
>   // { dg-require-effective-target-dfp }
> 
> which checks that the compiler supports modes SD, DD, and TD, which
> in turn are supported if ENABLE_DECIMAL_FLOAT is defined within the
> compiler.  That should not be defined for darwin; I'll take a look.

I built a cross cc1plus for x86_64-apple-darwin10 and got the behavior
I expected.  From $objdir/gcc:

elm3b149% fgrep -l ENABLE_DECIMAL_FLOAT *.h
auto-host.h:#define ENABLE_DECIMAL_FLOAT 0

elm3b149% echo "float x __attribute__((mode(DD)));" > x.c
elm3b149% ./cc1plus -quiet x.c
x.c:1:33: error: unable to emulate ‘DD’

Please try that little test with your cc1plus to see if the problem
is with your compiler not rejecting DD mode, or with the test
framework not handling it correctly.

Janis