Hi Arnd,
On Fri, Feb 16, 2018 at 4:27 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
> When we build this driver with on x86-32, gcc produces a false-positive warning:
>
> drivers/clk/renesas/clk-sh73a0.c: In function 'sh73a0_cpg_clocks_init':
> drivers/clk/renesas/clk-sh73a0.c:155:10: error: 'parent_name' may be used uninitialized in this function [-Werror=maybe-uninitialized]
> return clk_register_fixed_factor(NULL, name, parent_name, 0,
>
> We can work around that warning by adding a fake initialization, I tried
> and failed to come up with any better workaround. This is currently one
> of few remaining warnings for a 4.14.y randconfig build, so it would be
> good to also have it backported at least to that version. Older versions
> have more randconfig warnings, so we might not care.
>
> I had not noticed this earlier, because one patch in my randconfig test
> tree removes the '-ffreestanding' option on x86-32, and that avoids
> the warning. The -ffreestanding flag was originally global but moved
> into arch/i386 by Andi Kleen in commit 6edfba1b33c7 ("[PATCH] x86_64:
> Don't define string functions to builtin") as a 'temporary workaround'.
>
> Like many temporary hacks, this turned out to be rather long-lived, from
> all I can tell we still need a simple fix to asm/string_32.h before it
> can be removed, but I'm not sure about how to best do that.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Thanks, this is a known false positive.
Acked-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> drivers/clk/renesas/clk-sh73a0.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/clk/renesas/clk-sh73a0.c b/drivers/clk/renesas/clk-sh73a0.c
> index eea38f6ea77e..3892346c4fcc 100644
> --- a/drivers/clk/renesas/clk-sh73a0.c
> +++ b/drivers/clk/renesas/clk-sh73a0.c
> @@ -46,7 +46,7 @@ struct div4_clk {
> unsigned int shift;
> };
>
> -static struct div4_clk div4_clks[] = {
> +static const struct div4_clk div4_clks[] = {
This change is not part of the fix...
> { "zg", "pll0", CPG_FRQCRA, 16 },
> { "m3", "pll1", CPG_FRQCRA, 12 },
> { "b", "pll1", CPG_FRQCRA, 8 },
> @@ -79,7 +79,7 @@ sh73a0_cpg_register_clock(struct device_node *np, struct sh73a0_cpg *cpg,
> {
> const struct clk_div_table *table = NULL;
> unsigned int shift, reg, width;
> - const char *parent_name;
> + const char *parent_name = NULL;
> unsigned int mult = 1;
> unsigned int div = 1;
>
> @@ -135,7 +135,7 @@ sh73a0_cpg_register_clock(struct device_node *np, struct sh73a0_cpg *cpg,
> shift = 24;
> width = 5;
> } else {
> - struct div4_clk *c;
> + const struct div4_clk *c;
... and neither is this one.
>
> for (c = div4_clks; c->name; c++) {
> if (!strcmp(name, c->name)) {
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds