Re: -0.0L on Irix

[Tom G. Christensen]

On Mon, Jan 12, 2009 at 06:55:17AM -0700, Eric Blake wrote:
> According to Eric Blake on 1/9/2009 7:50 PM:
> > But so far, I've discovered this
> > about -0.0L on Irix 6.2:
> > 
> > With 'cc -n32', LDBL_MIN is a compile-time constant; but with 'gcc', I get
> > an error when trying to use it to initialize a global variable (note,
> > however, that it can be used inside the body of a method):
> > 
> > foo.c:9: error: initializer element is not constant
> > 
> > 
> > My conclusions: cc is buggy when representing -0.0L as a global variable,
> > but any variant that computes -0.0L during the body of a method works.
> 
> I tested on Irix 6.2, but suspect 6.5 will have similar behavior.  With
> this patch, both cc and gcc pass all 33 tests created by this:
> 
> gnulib-tool --create-testdir --dir=testdir2 --with-tests ceill floorl
> frexpl isnan isnanl ldexpl roundl signbit snprintf-posix sprintf-posix
> truncl vasnprintf-posix vasprintf-posix
> 
I've attempted to verify this on IRIX 6.5.30. Using MIPSpro 7.4.4m in std cc
mode all tests pass however in c99 mode test-roundl fails:
/bin/sh[9]: 6144914 Trace/BPT trap(coredump)
FAIL: test-roundl

Running it by hand gives:
$ ./test-roundl
Trace/BPT/RangeErr/DivZero/Ovflow trap (core dumped)

This test was also failing before but only with MIPSpro in c99 mode.

With gcc 4.3.1 one test fails:
test-ldexpl.c:129: assertion failed
/bin/sh[9]: 6244917 Abort(coredump)
FAIL: test-ldexpl

> whereas without the patch, cc compiled all tests but failed many of them,
> and gcc failed to even compile some of the tests.  I'm going ahead and
> committing it.
>
I've verified this for IRIX 6.5.30. With MIPSpro 7.4.4m in cc mode it
failed 7 tests and in c99 mode it failed 8 tests. With gcc 4.3.1 the
build failed in test-ceill.c

-tgc