Re: [PATCH] Use C99-compliant scanf under _GNU_SOURCE with C99/C++11 and higher.

[Andreas Schwab <schwab at suse dot de>]

On Dez 17 2018, Zack Weinberg <zackw@panix.com> wrote:

> On a related note, the interaction of the C99/not-C99 scanf redirect
> with the __LDBL_COMPAT scanf redirect was complicated, confusing,
> and possibly wrong.  The __ldbl_is_dbl cleanup (thanks to Gabriel
> Gomes for finishing that for me) has made it less complicated, but
> I'm still not 100% sure it's correct, and I do not have access to
> physical hardware for which __LDBL_COMPAT is relevant, so my ability
> to test it is limited.  Careful review (you'll want to read all of
> libio/bits/stdio-ldbl.h to understand what's going on, not just
> the diff) and maybe even some volunteer testing would be appreciated.

I have started a test build of your branch in
<https://build.opensuse.org/package/show/home:Andreas_Schwab:glibc:test/glibc>.

[  881s] In file included from <command-line>:
[  881s] ../sysdeps/ieee754/ldbl-opt/nldbl-sscanf.c:17:23: error: '_IO_sscanf' aliased to undefined symbol 'sscanf'
[  881s]  strong_alias (sscanf, _IO_sscanf)
[  881s]                        ^~~~~~~~~~
[  881s] ./../include/libc-symbols.h:140:26: note: in definition of macro '_strong_alias'
[  881s]    extern __typeof (name) aliasname __attribute__ ((alias (#name))) \
[  881s]                           ^~~~~~~~~
[  881s] ../sysdeps/ieee754/ldbl-opt/nldbl-sscanf.c:17:1: note: in expansion of macro 'strong_alias'
[  881s]  strong_alias (sscanf, _IO_sscanf)
[  881s]  ^~~~~~~~~~~~
[  881s] make[2]: *** [/home/abuild/rpmbuild/BUILD/glibc-2.28.9000.401.ge4bbeb76ee/cc-base/sysd-rules:831: /home/abuild/rpmbuild/BUILD/glibc-2.28.9000.401.ge4bbeb76ee/cc-base/math/nldbl-sscanf.oS] Error 1

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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