| Message ID | 20211104215047.663411-1-nathan@kernel.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | power: reset: ltc2952: Fix use of floating point literals | expand |
On Thu, Nov 4, 2021 at 2:51 PM Nathan Chancellor <nathan@kernel.org> wrote: > > A new commit in LLVM causes an error on the use of 'long double' when > '-mno-x87' is used, which the kernel does through an alias, > '-mno-80387' (see the LLVM commit below for more details around why it > does this). > > drivers/power/reset/ltc2952-poweroff.c:162:28: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it > data->wde_interval = 300L * 1E6L; > ^ > drivers/power/reset/ltc2952-poweroff.c:162:21: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it > data->wde_interval = 300L * 1E6L; > ^ > drivers/power/reset/ltc2952-poweroff.c:163:41: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it > data->trigger_delay = ktime_set(2, 500L*1E6L); > ^ > 3 errors generated. > > This happens due to the use of a 'long double' literal. The 'E6' part of > '1E6L' causes the literal to be a 'double' then the 'L' suffix promotes > it to 'long double'. > > There is no visible reason for floating point values in this driver, as > the values are only assigned to integer types. Use USEC_PER_SEC, which > is the same integer value as '1E6L', to avoid changing functionality but > fix the error. > > Fixes: 6647156c00cc ("power: reset: add LTC2952 poweroff driver") > Link: https://github.com/ClangBuiltLinux/linux/issues/1497 > Link: https://github.com/llvm/llvm-project/commit/a8083d42b1c346e21623a1d36d1f0cadd7801d83 > Signed-off-by: Nathan Chancellor <nathan@kernel.org> Thanks for the patch! Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> > --- > drivers/power/reset/ltc2952-poweroff.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/power/reset/ltc2952-poweroff.c b/drivers/power/reset/ltc2952-poweroff.c > index fbb344353fe4..ebe3f2bed4c5 100644 > --- a/drivers/power/reset/ltc2952-poweroff.c > +++ b/drivers/power/reset/ltc2952-poweroff.c > @@ -159,8 +159,8 @@ static void ltc2952_poweroff_kill(void) > > static void ltc2952_poweroff_default(struct ltc2952_poweroff *data) > { > - data->wde_interval = 300L * 1E6L; > - data->trigger_delay = ktime_set(2, 500L*1E6L); > + data->wde_interval = 300L * USEC_PER_SEC; > + data->trigger_delay = ktime_set(2, 500L * USEC_PER_SEC); > > hrtimer_init(&data->timer_trigger, CLOCK_MONOTONIC, HRTIMER_MODE_REL); > data->timer_trigger.function = ltc2952_poweroff_timer_trigger; > > base-commit: d4439a1189f93d0ac1eaf0197db8e6b3e197d5c7 > -- > 2.34.0.rc0 >
diff --git a/drivers/power/reset/ltc2952-poweroff.c b/drivers/power/reset/ltc2952-poweroff.c index fbb344353fe4..ebe3f2bed4c5 100644 --- a/drivers/power/reset/ltc2952-poweroff.c +++ b/drivers/power/reset/ltc2952-poweroff.c @@ -159,8 +159,8 @@ static void ltc2952_poweroff_kill(void) static void ltc2952_poweroff_default(struct ltc2952_poweroff *data) { - data->wde_interval = 300L * 1E6L; - data->trigger_delay = ktime_set(2, 500L*1E6L); + data->wde_interval = 300L * USEC_PER_SEC; + data->trigger_delay = ktime_set(2, 500L * USEC_PER_SEC); hrtimer_init(&data->timer_trigger, CLOCK_MONOTONIC, HRTIMER_MODE_REL); data->timer_trigger.function = ltc2952_poweroff_timer_trigger;
A new commit in LLVM causes an error on the use of 'long double' when '-mno-x87' is used, which the kernel does through an alias, '-mno-80387' (see the LLVM commit below for more details around why it does this). drivers/power/reset/ltc2952-poweroff.c:162:28: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it data->wde_interval = 300L * 1E6L; ^ drivers/power/reset/ltc2952-poweroff.c:162:21: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it data->wde_interval = 300L * 1E6L; ^ drivers/power/reset/ltc2952-poweroff.c:163:41: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it data->trigger_delay = ktime_set(2, 500L*1E6L); ^ 3 errors generated. This happens due to the use of a 'long double' literal. The 'E6' part of '1E6L' causes the literal to be a 'double' then the 'L' suffix promotes it to 'long double'. There is no visible reason for floating point values in this driver, as the values are only assigned to integer types. Use USEC_PER_SEC, which is the same integer value as '1E6L', to avoid changing functionality but fix the error. Fixes: 6647156c00cc ("power: reset: add LTC2952 poweroff driver") Link: https://github.com/ClangBuiltLinux/linux/issues/1497 Link: https://github.com/llvm/llvm-project/commit/a8083d42b1c346e21623a1d36d1f0cadd7801d83 Signed-off-by: Nathan Chancellor <nathan@kernel.org> --- drivers/power/reset/ltc2952-poweroff.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) base-commit: d4439a1189f93d0ac1eaf0197db8e6b3e197d5c7