diff options
| -rw-r--r-- | debug/warning-nop.c | 9 | ||||
| -rw-r--r-- | time/sys/time.h | 24 |
2 files changed, 33 insertions, 0 deletions
diff --git a/debug/warning-nop.c b/debug/warning-nop.c index 4ab7e182b7..9bd890a20b 100644 --- a/debug/warning-nop.c +++ b/debug/warning-nop.c @@ -67,4 +67,13 @@ nop (void) #define __builtin___strncpy_chk(dest, src, len, bos) NULL #define __builtin_object_size(bos, level) 0 +/* The code in sys/time.h that uses __warndecl has to work around GCC + bug 91554. The work-around is only effective if intptr_t is not + the same size as short. */ +#include <stdint.h> +_Static_assert (sizeof (intptr_t) != sizeof (short), + "workaround for GCC bug 91554 in sys/time.h" + " is only effective when short is smaller than a pointer"); + #include <string.h> +#include <sys/time.h> diff --git a/time/sys/time.h b/time/sys/time.h index 21fa9ed451..6b6f71d2e5 100644 --- a/time/sys/time.h +++ b/time/sys/time.h @@ -66,6 +66,30 @@ struct timezone extern int gettimeofday (struct timeval *__restrict __tv, void *__restrict __tz) __THROW __nonnull ((1)); +#if __GNUC_PREREQ (4,3) && defined __REDIRECT && defined __OPTIMIZE__ +/* Issue a warning for use of gettimeofday with a non-null __tz argument. */ +__warndecl (__warn_gettimeofday_nonnull_timezone, + "gettimeofday with non-null or non-constant timezone parameter;" + " this is obsolete and inaccurate, use localtime instead"); + +extern int __REDIRECT_NTH (__gettimeofday_alias, + (struct timeval *__restrict __tv, + void *__restrict __tz), gettimeofday) + __nonnull ((1)); + +/* The double cast below works around a limitation in __builtin_constant_p + in all released versions of GCC (as of August 2019). + See <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91554>. */ +__fortify_function int +__NTH (gettimeofday (struct timeval *__restrict __tv, void *__restrict __tz)) +{ + if (! (__builtin_constant_p ((short) (__intptr_t) __tz) && __tz == 0)) + __warn_gettimeofday_nonnull_timezone (); + + return __gettimeofday_alias (__tv, __tz); +} +#endif + #ifdef __USE_MISC /* Set the current time of day and timezone information. This call is restricted to the super-user. |