| Message ID | 20200428215804.48481-1-arnd@arndb.de (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
| Series | acpi: avoid uninialized-variable warning | expand |
On Wed, Apr 29, 2020 at 1:03 AM Arnd Bergmann <arnd@arndb.de> wrote: > > Older compilers like gcc-4.8 produce a bogus warning here > > In file included from include/linux/compiler_types.h:68:0, > from <command-line>:0: > drivers/acpi/property.c: In function 'acpi_data_prop_read': > include/linux/compiler-gcc.h:75:45: error: 'obj' may be used uninitialized in this function [-Werror=maybe-uninitialized] > #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) > ^ > drivers/acpi/property.c:934:27: note: 'obj' was declared here > const union acpi_object *obj; > ^ > > Ensure the output is always initialized even when returning an error > to avoid the warning. > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > drivers/acpi/property.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c > index e601c4511a8b..3aa71daeb0b4 100644 > --- a/drivers/acpi/property.c > +++ b/drivers/acpi/property.c > @@ -587,8 +587,10 @@ static int acpi_data_get_property_array(const struct acpi_device_data *data, > int ret, i; > > ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop); > - if (ret) > + if (ret && obj) { It changes semantics and requires obj to be non-NULL. Should be if (ret) { if (obj) *obj = NULL; return ret; } > + *obj = NULL; > return ret; > + } > > if (type != ACPI_TYPE_ANY) { > /* Check that all elements are of correct type. */ > -- > 2.26.0 >
diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c index e601c4511a8b..3aa71daeb0b4 100644 --- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -587,8 +587,10 @@ static int acpi_data_get_property_array(const struct acpi_device_data *data, int ret, i; ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop); - if (ret) + if (ret && obj) { + *obj = NULL; return ret; + } if (type != ACPI_TYPE_ANY) { /* Check that all elements are of correct type. */
Older compilers like gcc-4.8 produce a bogus warning here In file included from include/linux/compiler_types.h:68:0, from <command-line>:0: drivers/acpi/property.c: In function 'acpi_data_prop_read': include/linux/compiler-gcc.h:75:45: error: 'obj' may be used uninitialized in this function [-Werror=maybe-uninitialized] #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) ^ drivers/acpi/property.c:934:27: note: 'obj' was declared here const union acpi_object *obj; ^ Ensure the output is always initialized even when returning an error to avoid the warning. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/acpi/property.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)