| Message ID | a63cc9fe-b07a-3426-c530-46a02230663e@redhat.com |
|---|---|
| State | New |
| Headers | show |
On Thu, Jun 29, 2017 at 4:34 AM, Florian Weimer <fweimer@redhat.com> wrote: > On 06/29/2017 12:51 PM, H.J. Lu wrote: >> On Thu, Jun 29, 2017 at 12:31 AM, Florian Weimer <fweimer@redhat.com> wrote: >>> On 06/19/2017 03:48 PM, Florian Weimer wrote: >>>> 2017-06-19 Florian Weimer <fweimer@redhat.com> >>>> >>>> * stdio-common/tst-vfprintf-user-type.c: New file. >>>> * stdio-common/Makefile (tests): Add tst-vfprintf-user-type. >>> >>> I am going to commit this soon. >>> >> >> It fails on i686: >> >> tst-vfprintf-user-type.c: In function \u2018my_printf_function\u2019: >> tst-vfprintf-user-type.c:58:55: error: format \u2018%c\u2019 expects >> argument of type \u2018int\u2019, but argument 7 has type >> \u2018wchar_t {aka const long int}\u2019 [-Werror=format=] >> tst-vfprintf-user-type.c: In function \u2018my_arginfo_function\u2019: >> tst-vfprintf-user-type.c:112:55: error: format \u2018%c\u2019 expects >> argument of type \u2018int\u2019, but argument 7 has type >> \u2018wchar_t {aka const long int}\u2019 [-Werror=format=] > > Please try the attached patch. > > The need for the wint_t cast looks like a GCC bug. > Works for me. Thanks.
On Jun 29 2017, Florian Weimer <fweimer@redhat.com> wrote:
> The need for the wint_t cast looks like a GCC bug.
%lc wants wint_t.
Andreas.
On 06/29/2017 02:39 PM, Andreas Schwab wrote: > On Jun 29 2017, Florian Weimer <fweimer@redhat.com> wrote: > >> The need for the wint_t cast looks like a GCC bug. > > %lc wants wint_t. Sure, but why warn about this? I doubt there are any architectures which define wchar_t and wint_t in such a way that the variable arguments promotion diverges. Thanks, Florian
On Jun 29 2017, Florian Weimer <fweimer@redhat.com> wrote: > On 06/29/2017 02:39 PM, Andreas Schwab wrote: >> On Jun 29 2017, Florian Weimer <fweimer@redhat.com> wrote: >> >>> The need for the wint_t cast looks like a GCC bug. >> >> %lc wants wint_t. > > Sure, but why warn about this? Because the standard says so. > I doubt there are any architectures which define wchar_t and wint_t in > such a way that the variable arguments promotion diverges. The standard does not make that distinction. Andreas.
On Thu, 29 Jun 2017, Florian Weimer wrote: > On 06/29/2017 02:39 PM, Andreas Schwab wrote: > > On Jun 29 2017, Florian Weimer <fweimer@redhat.com> wrote: > > > >> The need for the wint_t cast looks like a GCC bug. > > > > %lc wants wint_t. > > Sure, but why warn about this? I doubt there are any architectures > which define wchar_t and wint_t in such a way that the variable > arguments promotion diverges. The different signedness can break the ABI, if you pass a negative wchar_t (so sign-extended to 64-bit) but the called function expects wint_t (zero-extended to 64-bit). (E.g., the powerpc64 ABI requires such zero-extension of an unsigned argument.)
On 06/29/2017 04:37 PM, Joseph Myers wrote: > On Thu, 29 Jun 2017, Florian Weimer wrote: > >> On 06/29/2017 02:39 PM, Andreas Schwab wrote: >>> On Jun 29 2017, Florian Weimer <fweimer@redhat.com> wrote: >>> >>>> The need for the wint_t cast looks like a GCC bug. >>> >>> %lc wants wint_t. >> >> Sure, but why warn about this? I doubt there are any architectures >> which define wchar_t and wint_t in such a way that the variable >> arguments promotion diverges. > > The different signedness can break the ABI, if you pass a negative wchar_t > (so sign-extended to 64-bit) but the called function expects wint_t > (zero-extended to 64-bit). (E.g., the powerpc64 ABI requires such > zero-extension of an unsigned argument.) I see. Based on what is said in the standard, the cast is indeed required. That's rather unfortunate from a programmer convenience point of view. Florian
vfprintf: Fix tst-vfprintf-mbs-prec and tst-vfprintf-user-type 2017-06-29 Florian Weimer <fweimer@redhat.com> * stdio-common/tst-vfprintf-user-type.c (my_printf_function): Adjust format string. * stdio-common/Makefile (tst-vfprintf-mbs-prec.out): Add locale dependency. diff --git a/stdio-common/Makefile b/stdio-common/Makefile index 309d83e..622a85f 100644 --- a/stdio-common/Makefile +++ b/stdio-common/Makefile @@ -87,6 +87,7 @@ $(objpfx)tst-grouping.out: $(gen-locales) $(objpfx)tst-sprintf.out: $(gen-locales) $(objpfx)tst-sscanf.out: $(gen-locales) $(objpfx)tst-swprintf.out: $(gen-locales) +$(objpfx)tst-vfprintf-mbs-prec.out: $(gen-locales) endif tst-printf-bz18872-ENV = MALLOC_TRACE=$(objpfx)tst-printf-bz18872.mtrace diff --git a/stdio-common/tst-vfprintf-user-type.c b/stdio-common/tst-vfprintf-user-type.c index e9596c3..91ea02f 100644 --- a/stdio-common/tst-vfprintf-user-type.c +++ b/stdio-common/tst-vfprintf-user-type.c @@ -29,6 +29,7 @@ #include <support/check.h> #include <support/support.h> #include <support/test-driver.h> +#include <wchar.h> /* Initialized by do_test using register_printf_type. */ static int user_type; @@ -55,8 +56,9 @@ my_printf_function (FILE *fp, const struct printf_info *info, const void *const *args) { if (test_verbose > 0) - printf ("info: %s (%p, %p, {%p}@%p) called for %%%c (prec %d)\n", - __func__, fp, info, args[0], args, info->spec, info->prec); + printf ("info: %s (%p, %p, {%p}@%p) called for %%%lc (prec %d)\n", + __func__, fp, info, args[0], args, (wint_t) info->spec, + info->prec); TEST_VERIFY (info->spec == 'P'); size_t nargs; @@ -109,8 +111,9 @@ my_arginfo_function (const struct printf_info *info, if (info->spec != 'P') return -1; if (test_verbose > 0) - printf ("info: %s (%p, %zu, %p, %p) called for %%%c (prec %d)\n", - __func__, info, n, argtypes, size, info->spec, info->prec); + printf ("info: %s (%p, %zu, %p, %p) called for %%%lc (prec %d)\n", + __func__, info, n, argtypes, size, (wint_t) info->spec, + info->prec); TEST_VERIFY_EXIT (n >= 1); size_t nargs;