const-qualify variable to suppress compiler warning

[escherstair]

I get a warning/suggestion from the compiler because in the following function https://github.com/ARM-software/CMSIS_5/blob/a75f01746df18bb5b929dfb8dc6c9407fac3a0f3/CMSIS/Core/Include/core_cm7.h#L2195-L2199

in the line

  uint32_t *vectors = (uint32_t *)SCB->VTOR;

the pointer vectors can/should be defines as pointer-to-const

  const uint32_t *vectors = (const uint32_t *)SCB->VTOR;

I think that the same change can be applied to all the other core_cmXXX.h files

[JonatanAntoni]

Hi @escherstair,

Thanks for pointing this out. I moved your proposal to CMSIS 6 as this should be the place to make such enhancements.

I wonder if uint32_t is the correct type at all. Unfortunately, changing type to void(*VECTOR_TABLE_Type)(void) would be a breaking change.

[ReinhardKeil]

@escherstair which compiler are you using. SCB->VTOR can also point to a RAM based vector table. Is in this case (const uint32_t *) the right definition?

It may depend therefore depend on global compiler optimizations and other usage of SCB->VTOR in your application.

[escherstair]

@ReinhardKeil the suggestion is only related to adding const. The type was uint32_t* and I don't want to change it. The function

__STATIC_INLINE uint32_t __NVIC_GetVector(IRQn_Type IRQn)
{
  uint32_t *vectors = (uint32_t *)SCB->VTOR;
  return vectors[(int32_t)IRQn + NVIC_USER_IRQ_OFFSET];
}

doesn't change the value pointed by *vectors, but it returns it. And so a pointer-to-const should be preferred.

I use AC6 with maximum warnings, combined with cppcheck + clang-tidy analysis.