On Tue, 19 Sep 2023 22:44:28 +0200,
Nick Desaulniers wrote:
>
> On Mon, Sep 18, 2023 at 10:51:29AM +0100, Richard Fitzgerald wrote:
(snip)
> > +static void cirrus_scodec_test_set_gpio_ref_arg(struct software_node_ref_args *arg,
> > + int gpio_num)
> > +{
> > + struct software_node_ref_args template =
> > + SOFTWARE_NODE_REFERENCE(&cirrus_scodec_test_gpio_swnode, gpio_num, 0);
>
> I'm observing the following error when building with:
>
> $ make LLVM=1 -j128 allmodconfig sound/pci/hda/cirrus_scodec_test.o
>
> sound/pci/hda/cirrus_scodec_test.c:151:60: error: initializer element is not a compile-time constant
> 151 | SOFTWARE_NODE_REFERENCE(&cirrus_scodec_test_gpio_swnode, gpio_num, 0);
> | ^~~~~~~~
> /builds/linux/include/linux/property.h:291:37: note: expanded from macro 'SOFTWARE_NODE_REFERENCE'
> 291 | .nargs = ARRAY_SIZE(((u64[]){ 0, ##__VA_ARGS__ })) - 1, \
> | ^~~~~~~~~~~
> /builds/linux/include/linux/kernel.h:57:75: note: expanded from macro 'ARRAY_SIZE'
> 57 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
> | ^~~
> /builds/linux/include/linux/compiler.h:228:59: note: expanded from macro '__must_be_array'
> 228 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
> | ^
> /builds/linux/include/linux/compiler_types.h:366:63: note: expanded from macro '__same_type'
> 366 | #define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
> | ^
> /builds/linux/include/linux/build_bug.h:16:62: note: expanded from macro 'BUILD_BUG_ON_ZERO'
> 16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
> | ^
Hm, this looks like some inconsistent handling of the temporary array
passed to ARRAY_SIZE() in the SOFTWARE_NODE_REFERENCE macro. LLVM
can't treat it if it contains a variable in the given array, while GCC
doesn't care.
A hackish workaround would be the patch like below, but it's really
ugly. Ideally speaking, it should be fixed in linux/properties.h, but
I have no idea how to fix there for LLVM.
Adding more relevant people to Cc.
thanks,
Takashi
--- a/sound/pci/hda/cirrus_scodec_test.c
+++ b/sound/pci/hda/cirrus_scodec_test.c
@@ -148,8 +148,9 @@ static void cirrus_scodec_test_set_gpio_ref_arg(struct software_node_ref_args *a
int gpio_num)
{
struct software_node_ref_args template =
- SOFTWARE_NODE_REFERENCE(&cirrus_scodec_test_gpio_swnode, gpio_num, 0);
+ SOFTWARE_NODE_REFERENCE(&cirrus_scodec_test_gpio_swnode, 0, 0);
+ template.args[0] = gpio_num;
*arg = template;
}
