| Message ID | 20240502074158.85800-1-philmd@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | hw/input/tsc2005: Fix -Wchar-subscripts warning in tsc2005_txrx() | expand |
On Thu, 2 May 2024 at 08:42, Philippe Mathieu-Daudé <philmd@linaro.org> wrote: > > Check the function index is not negative and use an unsigned > variable to avoid the following warning with GCC 13.2.0: > > [666/5358] Compiling C object libcommon.fa.p/hw_input_tsc2005.c.o > hw/input/tsc2005.c: In function 'tsc2005_timer_tick': > hw/input/tsc2005.c:416:26: warning: array subscript has type 'char' [-Wchar-subscripts] > 416 | s->dav |= mode_regs[s->function]; > | ~^~~~~~~~~~ > > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> > --- > hw/input/tsc2005.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/hw/input/tsc2005.c b/hw/input/tsc2005.c > index 941f163d36..fa93eb5d25 100644 > --- a/hw/input/tsc2005.c > +++ b/hw/input/tsc2005.c > @@ -406,6 +406,7 @@ uint32_t tsc2005_txrx(void *opaque, uint32_t value, int len) > static void tsc2005_timer_tick(void *opaque) > { > TSC2005State *s = opaque; > + unsigned func_idx; > > /* Timer ticked -- a set of conversions has been finished. */ > > @@ -413,7 +414,9 @@ static void tsc2005_timer_tick(void *opaque) > return; > > s->busy = false; > - s->dav |= mode_regs[s->function]; > + assert(s->function >= 0); > + func_idx = s->function; > + s->dav |= mode_regs[func_idx]; > s->function = -1; > tsc2005_pin_update(s); > } This code is in a deprecated device, but it makes sense to avoid the compiler warning in the meantime. (I'm curious why this only comes up now, since I thought this warning had been around for a while. Maybe gcc 13 is applying it in a wider range of situations.) If we're going to assert I think we might as well catch array overruns in both directions: unsigned int function = s->function; assert(function < ARRAY_SIZE(mode_regs); s->dav |= mode_regs[function]; thanks -- PMM
diff --git a/hw/input/tsc2005.c b/hw/input/tsc2005.c index 941f163d36..fa93eb5d25 100644 --- a/hw/input/tsc2005.c +++ b/hw/input/tsc2005.c @@ -406,6 +406,7 @@ uint32_t tsc2005_txrx(void *opaque, uint32_t value, int len) static void tsc2005_timer_tick(void *opaque) { TSC2005State *s = opaque; + unsigned func_idx; /* Timer ticked -- a set of conversions has been finished. */ @@ -413,7 +414,9 @@ static void tsc2005_timer_tick(void *opaque) return; s->busy = false; - s->dav |= mode_regs[s->function]; + assert(s->function >= 0); + func_idx = s->function; + s->dav |= mode_regs[func_idx]; s->function = -1; tsc2005_pin_update(s); }
Check the function index is not negative and use an unsigned variable to avoid the following warning with GCC 13.2.0: [666/5358] Compiling C object libcommon.fa.p/hw_input_tsc2005.c.o hw/input/tsc2005.c: In function 'tsc2005_timer_tick': hw/input/tsc2005.c:416:26: warning: array subscript has type 'char' [-Wchar-subscripts] 416 | s->dav |= mode_regs[s->function]; | ~^~~~~~~~~~ Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> --- hw/input/tsc2005.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)