[LTP] [PATCH] Define __NR_futex to be __NR_futex_time64 on riscv32

[Petr Vorel]

Hi Khem,

> RISCV glibc has decided to use 64bit time_t from get go unlike
> other 32bit architecture therefore aliasing __NR_futex to
> __NR_futex_time64 helps avoid the below errors on rv32

> tst_checkpoint.c:99:17: error: use of undeclared identifier 'SYS_futex'

Thanks for your fix.

BTW, out of curiosity, is Risc-v 32 bit merged into glibc master?

I found a patch from Alistair Francis from January, which implements what you claim:
https://sourceware.org/legacy-ml/libc-alpha/2020-01/msg00205.html
...
+/* RV32 and RV64 both use 64-bit time_t */
+#define __TIMESIZE	64
diff --git a/sysdeps/unix/sysv/linux/riscv/bits/typesizes.h b/sysdeps/unix/sysv/linux/riscv/bits/typesizes.h
...

(part of https://patches-gcc.linaro.org/project/glibc/list/?series=21554
patchset) but it hasn't been merged yet to master.

+ There is older patchset from Zong Li, not yet merged.
https://patches-gcc.linaro.org/cover/12952/

> Signed-off-by: Khem Raj <raj.khem@gmail.com>
> ---
>  lib/tst_checkpoint.c                        | 4 ++++
>  testcases/kernel/syscalls/clone/clone08.c   | 4 ++++
>  testcases/kernel/syscalls/futex/futextest.h | 4 ++++
>  3 files changed, 12 insertions(+)

> diff --git a/lib/tst_checkpoint.c b/lib/tst_checkpoint.c
> index 5e5b11496c..0388e9db2f 100644
> --- a/lib/tst_checkpoint.c
> +++ b/lib/tst_checkpoint.c
> @@ -21,6 +21,10 @@
>   * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
>   */

> +#if !defined(__NR_futex) && defined(__riscv) && __riscv_xlen == 32
> +# define __NR_futex __NR_futex_time64
> +#endif

I guess this should go to include/lapi/futex.h, so we don't repeat ourselves.
(and clone08.c needs to include it, others already do).

...

Kind regards,
Petr