Re: [PATCH] crypto: ccp: Remove forward declaration

From: Nathan Chancellor
Date: Mon Sep 24 2018 - 15:40:49 EST


On Mon, Sep 24, 2018 at 07:18:23PM +0000, Gary R Hook wrote:
> On 09/24/2018 12:26 PM, Nathan Chancellor wrote:
> > Clang emits a warning about this construct:
> >
> > drivers/crypto/ccp/sp-platform.c:36:36: warning: tentative array
> > definition assumed to have one element
> > static const struct acpi_device_id sp_acpi_match[];
> > ^
> > 1 warning generated.
> >
> > Just remove the forward declarations and move the initializations up
> > so that they can be used in sp_get_of_version and sp_get_acpi_version.
>
> I'm not going to out and out object to this just yet.
>
> I am not a clang expert. Can you please provide a make command that
> would explain how you precipitated this complaint?
>

Hi Gary,

I can produce the warning with Clang 6.0 using the following set of
commands:

make ARCH=arm64 CC=clang CROSS_COMPILE=aarch64-linux-gnu- allyesconfig
./scripts/config -d CONFIG_CPU_BIG_ENDIAN
make ARCH=arm64 CC=clang CROSS_COMPILE=aarch64-linux-gnu- olddefconfig
make ARCH=arm64 CC=clang CROSS_COMPILE=aarch64-linux-gnu- drivers/crypto/ccp/sp-platform.o

Nathan

>
> > Reported-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> > Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> > ---
> > drivers/crypto/ccp/sp-platform.c | 53 +++++++++++++++-----------------
> > 1 file changed, 25 insertions(+), 28 deletions(-)
> >
> > diff --git a/drivers/crypto/ccp/sp-platform.c b/drivers/crypto/ccp/sp-platform.c
> > index 71734f254fd1..b75dc7db2d4a 100644
> > --- a/drivers/crypto/ccp/sp-platform.c
> > +++ b/drivers/crypto/ccp/sp-platform.c
> > @@ -33,8 +33,31 @@ struct sp_platform {
> > unsigned int irq_count;
> > };
> >
> > -static const struct acpi_device_id sp_acpi_match[];
> > -static const struct of_device_id sp_of_match[];
> > +static const struct sp_dev_vdata dev_vdata[] = {
> > + {
> > + .bar = 0,
> > +#ifdef CONFIG_CRYPTO_DEV_SP_CCP
> > + .ccp_vdata = &ccpv3_platform,
> > +#endif
> > + },
> > +};
> > +
> > +#ifdef CONFIG_ACPI
> > +static const struct acpi_device_id sp_acpi_match[] = {
> > + { "AMDI0C00", (kernel_ulong_t)&dev_vdata[0] },
> > + { },
> > +};
> > +MODULE_DEVICE_TABLE(acpi, sp_acpi_match);
> > +#endif
> > +
> > +#ifdef CONFIG_OF
> > +static const struct of_device_id sp_of_match[] = {
> > + { .compatible = "amd,ccp-seattle-v1a",
> > + .data = (const void *)&dev_vdata[0] },
> > + { },
> > +};
> > +MODULE_DEVICE_TABLE(of, sp_of_match);
> > +#endif
> >
> > static struct sp_dev_vdata *sp_get_of_version(struct platform_device *pdev)
> > {
> > @@ -201,32 +224,6 @@ static int sp_platform_resume(struct platform_device *pdev)
> > }
> > #endif
> >
> > -static const struct sp_dev_vdata dev_vdata[] = {
> > - {
> > - .bar = 0,
> > -#ifdef CONFIG_CRYPTO_DEV_SP_CCP
> > - .ccp_vdata = &ccpv3_platform,
> > -#endif
> > - },
> > -};
> > -
> > -#ifdef CONFIG_ACPI
> > -static const struct acpi_device_id sp_acpi_match[] = {
> > - { "AMDI0C00", (kernel_ulong_t)&dev_vdata[0] },
> > - { },
> > -};
> > -MODULE_DEVICE_TABLE(acpi, sp_acpi_match);
> > -#endif
> > -
> > -#ifdef CONFIG_OF
> > -static const struct of_device_id sp_of_match[] = {
> > - { .compatible = "amd,ccp-seattle-v1a",
> > - .data = (const void *)&dev_vdata[0] },
> > - { },
> > -};
> > -MODULE_DEVICE_TABLE(of, sp_of_match);
> > -#endif
> > -
> > static struct platform_driver sp_platform_driver = {
> > .driver = {
> > .name = "ccp",
> >
>