[PATCH 05/10] Return EXIT_UNSUPPORTED if __builtin_add_overflow unavailable
H.J. Lu
hjl.tools@gmail.com
Sat Dec 14 12:14:32 GMT 2024
On Sat, Dec 14, 2024 at 5:38 PM Sam James <sam@gentoo.org> wrote:
>
> "H.J. Lu" <hjl.tools@gmail.com> writes:
>
> > Since GCC 4.9 doesn't have __builtin_add_overflow:
> >
> > In file included from tst-stringtable.c:180:0:
> > stringtable.c: In function ‘stringtable_finalize’:
> > stringtable.c:185:7: error: implicit declaration of function ‘__builtin_add_overflow’ [-Werror=implicit-function-declaration]
> > else if (__builtin_add_overflow (previous->offset,
> > ^
> >
> > return EXIT_UNSUPPORTED for GCC 4.9 or older.
> >
> > Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
> > ---
> > elf/tst-stringtable.c | 10 ++++++++++
> > io/tst-utimensat-skeleton.c | 5 +++++
> > sysdeps/unix/sysv/linux/tst-getdents64.c | 7 +++++++
> > time/tst-ctime.c | 5 +++++
> > time/tst-difftime.c | 7 ++++++-
> > time/tst-mktime4.c | 8 +++++++-
> > 6 files changed, 40 insertions(+), 2 deletions(-)
> >
> > diff --git a/elf/tst-stringtable.c b/elf/tst-stringtable.c
> > index e18496f3f1..a0e358f02a 100644
> > --- a/elf/tst-stringtable.c
> > +++ b/elf/tst-stringtable.c
> > @@ -17,6 +17,7 @@
> >
> > #include <array_length.h>
> > #include <stdlib.h>
> > +#if __GNUC_PREREQ (5, 0)
> > #include <string.h>
> > #include <stringtable.h>
> > #include <support/check.h>
> > @@ -179,3 +180,12 @@ do_test (void)
> > #define _(arg) arg
> > #include "stringtable.c"
> > #include "stringtable_free.c"
> > +#else
> > +#include <support/test-driver.h>
> > +
> > +int
> > +main (void)
> > +{
> > + return EXIT_UNSUPPORTED;
> > +}
> > +#endif
> > diff --git a/io/tst-utimensat-skeleton.c b/io/tst-utimensat-skeleton.c
> > index 290ed81c9b..1386fa3c8f 100644
> > --- a/io/tst-utimensat-skeleton.c
> > +++ b/io/tst-utimensat-skeleton.c
> > @@ -20,6 +20,7 @@
> > #include <inttypes.h>
> > #include <support/support.h>
> > #include <support/temp_file.h>
> > +#include <support/test-driver.h>
> > #include <stdio.h>
> >
> > static int temp_fd = -1;
> > @@ -72,6 +73,7 @@ do_test (void)
> > for (int i = 0; i < array_length (tests); i++)
> > {
> > /* Check if we run on port with 32 bit time_t size. */
> > +#if __GNUC_PREREQ (5, 0)
> > time_t t;
> > if (__builtin_add_overflow (tests[i].v1, 0, &t)
> > || __builtin_add_overflow (tests[i].v2, 0, &t))
> > @@ -80,6 +82,9 @@ do_test (void)
> > "time_t overflows\n", i, tests[i].v1, tests[i].v2);
> > continue;
> > }
> > +#else
> > + return EXIT_UNSUPPORTED;
> > +#endif
> >
> > if (tests[i].v1 >= 0x100000000LL && !y2106)
> > {
> > diff --git a/sysdeps/unix/sysv/linux/tst-getdents64.c b/sysdeps/unix/sysv/linux/tst-getdents64.c
> > index 3dd22a4e03..ba66d49a2e 100644
> > --- a/sysdeps/unix/sysv/linux/tst-getdents64.c
> > +++ b/sysdeps/unix/sysv/linux/tst-getdents64.c
> > @@ -30,6 +30,7 @@
> > #include <sys/mman.h>
> > #include <unistd.h>
> >
> > +#if __GNUC_PREREQ (5, 0)
> > /* Called by large_buffer_checks below. */
> > static void
> > large_buffer_check (int fd, char *large_buffer, size_t large_buffer_size)
> > @@ -85,6 +86,12 @@ do_test_large_size (void)
> >
> > xclose (fd);
> > }
> > +#else
> > +static void
> > +do_test_large_size (void)
> > +{
> > +}
> > +#endif
> >
> > static void
> > do_test_by_size (size_t buffer_size)
> > diff --git a/time/tst-ctime.c b/time/tst-ctime.c
> > index 8debf15004..f997a93801 100644
> > --- a/time/tst-ctime.c
> > +++ b/time/tst-ctime.c
> > @@ -19,6 +19,7 @@
> > #include <time.h>
> > #include <stdlib.h>
> > #include <support/check.h>
> > +#include <support/test-driver.h>
> >
> > static int
> > do_test (void)
> > @@ -54,8 +55,12 @@ do_test (void)
> >
> > /* Check if we run on port with 32 bit time_t size */
> > time_t tov;
> > +#if __GNUC_PREREQ (5, 0)
> > if (__builtin_add_overflow (t, 1, &tov))
> > return 0;
> > +#else
> > + return EXIT_UNSUPPORTED;
> > +#endif
> >
> > /* Check if the time is converted after 32 bit time_t overflow. */
> > str = ctime (&tov);
> > diff --git a/time/tst-difftime.c b/time/tst-difftime.c
> > index 5043d55087..94723aa906 100644
> > --- a/time/tst-difftime.c
> > +++ b/time/tst-difftime.c
> > @@ -18,6 +18,7 @@
> >
> > #include <time.h>
> > #include <support/check.h>
> > +#include <support/test-driver.h>
> >
> > static void
> > test_difftime_helper (time_t t1, time_t t0, double exp_val)
> > @@ -37,10 +38,14 @@ do_test (void)
> > test_difftime_helper (t - 1800, t + 1800, -3600.0);
> >
> > t = 0x7FFFFFFF;
> > - /* Check if we run on port with 32 bit time_t size */
> > time_t tov;
> > +#if __GNUC_PREREQ (5, 0)
> > + /* Check if we run on port with 32 bit time_t size */
> > if (__builtin_add_overflow (t, 1, &tov))
> > return 0;
> > +#else
> > + return EXIT_UNSUPPORTED;
> > +#endif
> >
> > /* Check if the time is converted after 32 bit time_t overflow. */
> > test_difftime_helper (t + 1800, t - 1800, 3600.0);
> > diff --git a/time/tst-mktime4.c b/time/tst-mktime4.c
> > index 505d9fcc2e..50d3acd375 100644
> > --- a/time/tst-mktime4.c
> > +++ b/time/tst-mktime4.c
> > @@ -19,6 +19,7 @@
> > #include <time.h>
> > #include <stdlib.h>
> > #include <support/check.h>
> > +#include <support/test-driver.h>
> >
> > const struct tm tm0 =
> > {
> > @@ -55,11 +56,16 @@ const struct tm tm32bitmax =
> > static
> > int test_mktime_helper (struct tm *tm, long long int exp_val, int line)
> > {
> > - time_t result, t;
> > + time_t result;
> >
> > +#if __GNUC_PREREQ (5, 0)
> > /* Check if we run on port with 32 bit time_t size. */
> > + time_t t;
> > if (__builtin_add_overflow (exp_val, 0, &t))
> > return 0;
> > +#else
> > + return EXIT_UNSUPPORTED;
> > +#endif
> >
> > result = mktime (tm);
> > if (result == (time_t) -1)
>
> Can you do early exit instead please?
>
> #if ! ...
> return ...
> #endif
Changed in v2. __builtin_add_overflow must be inside of
#if __GNUC_PREREQ (5, 0)
#endif
since it is unavailable before GCC 5.
Thanks.
--
H.J.
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