| Message ID | 20170714093129.1366900-4-arnd@arndb.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, 2017-07-14 at 11:31 +0200, Arnd Bergmann wrote: > When we pass the result of a multiplication as the timeout, we > can get a warning: > > drivers/mmc/host/bcm2835.c:596:149: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context] > drivers/mfd/arizona-core.c:247:195: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context] > > This is easy to avoid by comparing the timeout to zero instead, > making it a boolean expression. Perhaps this is better as != 0 if the multiply is signed. > diff --git a/include/linux/iopoll.h b/include/linux/iopoll.h [] > @@ -48,7 +48,8 @@ > (val) = op(addr); \ > if (cond) \ > break; \ > - if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) { \ > + if ((timeout_us) > 0 && \ > + ktime_compare(ktime_get(), timeout) > 0) { \ > (val) = op(addr); \ > break; \ > } \ etc...
On Fri, Jul 14, 2017 at 11:55 AM, Joe Perches <joe@perches.com> wrote: > On Fri, 2017-07-14 at 11:31 +0200, Arnd Bergmann wrote: >> When we pass the result of a multiplication as the timeout, we >> can get a warning: >> >> drivers/mmc/host/bcm2835.c:596:149: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context] >> drivers/mfd/arizona-core.c:247:195: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context] >> >> This is easy to avoid by comparing the timeout to zero instead, >> making it a boolean expression. > > Perhaps this is better as != 0 if the multiply is signed. I thought about that, but decided that as a negative timeout_us already gives us rather random behavior (ktime_add_us() takes an unsigned argument), the '>' comparison gives a more well-defined result by ignoring the timeout. Arnd
diff --git a/include/linux/iopoll.h b/include/linux/iopoll.h index d29e1e21bf3f..7a17ba02253b 100644 --- a/include/linux/iopoll.h +++ b/include/linux/iopoll.h @@ -48,7 +48,8 @@ (val) = op(addr); \ if (cond) \ break; \ - if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) { \ + if ((timeout_us) > 0 && \ + ktime_compare(ktime_get(), timeout) > 0) { \ (val) = op(addr); \ break; \ } \ @@ -82,7 +83,8 @@ (val) = op(addr); \ if (cond) \ break; \ - if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) { \ + if ((timeout_us) > 0 && \ + ktime_compare(ktime_get(), timeout) > 0) { \ (val) = op(addr); \ break; \ } \ diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 1474ab0a3922..0889dbf37161 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -129,7 +129,7 @@ struct reg_sequence { break; \ if (cond) \ break; \ - if ((timeout_us) && \ + if ((timeout_us) > 0 && \ ktime_compare(ktime_get(), __timeout) > 0) { \ __ret = regmap_read((map), (addr), &(val)); \ break; \
When we pass the result of a multiplication as the timeout, we can get a warning: drivers/mmc/host/bcm2835.c:596:149: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context] drivers/mfd/arizona-core.c:247:195: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context] This is easy to avoid by comparing the timeout to zero instead, making it a boolean expression. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- include/linux/iopoll.h | 6 ++++-- include/linux/regmap.h | 2 +- 2 files changed, 5 insertions(+), 3 deletions(-)