linux/tools/include
Rikard Falkeborn f747e6667e linux/bits.h: fix compilation error with GENMASK
GENMASK() has an input check which uses __builtin_choose_expr() to
enable a compile time sanity check of its inputs if they are known at
compile time.

However, it turns out that __builtin_constant_p() does not always return
a compile time constant [0].  It was thought this problem was fixed with
gcc 4.9 [1], but apparently this is not the case [2].

Switch to use __is_constexpr() instead which always returns a compile time
constant, regardless of its inputs.

Link: https://lore.kernel.org/lkml/42b4342b-aefc-a16a-0d43-9f9c0d63ba7a@rasmusvillemoes.dk [0]
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=19449 [1]
Link: https://lore.kernel.org/lkml/1ac7bbc2-45d9-26ed-0b33-bf382b8d858b@I-love.SAKURA.ne.jp [2]
Link: https://lkml.kernel.org/r/20210511203716.117010-1-rikard.falkeborn@gmail.com
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Yury Norov <yury.norov@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-22 15:09:07 -10:00
..
asm tools arch: Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy' 2021-05-10 09:01:00 -03:00
asm-generic Merge branch 'akpm' (patches from Andrew) 2021-05-07 00:34:51 -07:00
linux linux/bits.h: fix compilation error with GENMASK 2021-05-22 15:09:07 -10:00
nolibc tools/nolibc: Fix position of -lgcc in the documented example 2021-01-21 10:06:45 -08:00
tools tools: bpf: fix license for a compat header file 2018-09-19 23:49:58 +02:00
trace/events tools/lib/lockdep: Remove private kernel headers 2017-06-05 09:28:14 +02:00
uapi tools headers UAPI: Sync perf_event.h with the kernel sources 2021-05-10 09:01:01 -03:00
vdso tools headers: Synchronize linux/bits.h with the kernel sources 2020-04-14 11:40:05 -03:00