Re: declaration meaning

Darko schrieb:
If this works, then it's a work of art. :) Of course - if one was to
declare it as a variable, it would get a compiler error. However,
declaring it in a structure doesn't do the allocating itself, we just
get a name we later hold for when referring to (m)allocated memory.
Genialno. :) So, it actually works only for structs?

work of art? I'd say that's a landmine.

- Anyone unsuspiciously using a memcpy(pX,pFoo,sizeof(*pFoo)) will get surprising results.

- Using malloc, one must take into account that the storage for the first element is covered by sizeof(stuct message) while the rest is not.

- for copying you should at least provide a size_t len member to determine the "extra" space.

- it makes your code wide open for heap-overflow attacks and code injection exploits.

- It's impossible to have these objects on the stack, even if the compiler permits it.

- Consider using #pragma pack(1) struct ... #pragma pack()
this will provide you at least with defined memory-layouts you are using reinterpret-casts to the "char" data, even if packing was modified from somewhere else. (cc options, foreign headers)

I'd suggest not to use this construct even if it's convenient.

<flame mode="plenty">
variable sized array are pure evil
</flame>
.

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