[9fans] 6c bug?

[erik quanstrom]

for p = uchar*, Nbus==256,

if((uint)p[1] >= Nbus){

generates

warning: ./mp.c:212 useless or misleading comparison: UCHAR >= 0x100

i'm pretty sure that 6c is incorrectly issuing the diagnostic before
applying the cast. (the cast is there to shut the compiler up.)

- erik

[Bruce Ellis]

what values of p[1] do you expect the test to be of use?

Post by erik quanstrom
for p = uchar*, Nbus==256,
               if((uint)p[1] >= Nbus){
generates
       warning: ./mp.c:212 useless or misleading comparison: UCHAR >= 0x100
i'm pretty sure that 6c is incorrectly issuing the diagnostic before
applying the cast.  (the cast is there to shut the compiler up.)
- erik

[erik quanstrom]

Post by Bruce Ellis
what values of p[1] do you expect the test to be of use?

Post by erik quanstrom
for p = uchar*, Nbus==256,
               if((uint)p[1] >= Nbus){
generates
       warning: ./mp.c:212 useless or misleading comparison: UCHAR >= 0x100
i'm pretty sure that 6c is incorrectly issuing the diagnostic before
applying the cast.  (the cast is there to shut the compiler up.)

it is not a given that Nbus >= 255.

- erik

[Bruce Ellis]

for the example you gave the diagnostic is correct.

Post by erik quanstrom

Post by Bruce Ellis
what values of p[1] do you expect the test to be of use?

Post by erik quanstrom
for p = uchar*, Nbus==256,
               if((uint)p[1] >= Nbus){
generates
       warning: ./mp.c:212 useless or misleading comparison: UCHAR >= 0x100
i'm pretty sure that 6c is incorrectly issuing the diagnostic before
applying the cast.  (the cast is there to shut the compiler up.)

it is not a given that Nbus >= 255.
- erik

[erik quanstrom]

Post by Bruce Ellis
for the example you gave the diagnostic is correct.

pffft. you're right.

- erik