Re: libgpg-error 1.61: t-printf failure on powerpc64-linux

NIIBE Yutaka via Gnupg-users <[email protected]> Wed, 29 Jul 2026 16:11:02 +0900
Newsgroups gmane.comp.encryption.gpg.user
Message-ID <[email protected]>
Hello,

"C. Neidahl" <[email protected]> wrote:
> I suppose the most exact check for this situation would have to inspect 
> some more LDBL_* 
> defines, otherwise 128-bit IEEE-backed long double 
> would end up not getting checked.

I see the situation.

In gnulib, to detect "double double" situation, it checks:

	LDBL_MANT_DIG == 106

I wonder if it works better than use of LDBL_IS_IEC_60559 macro.

When we use the macro LDBL_IS_IEC_60559 (new for C23), if there is an
environment (of PowerPC 64 architecture) where LDBL_IS_IEC_60559 is not
defined (say, compiler is older) but actually uses standard floating
point, I'm afraid it skips the test.
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