void* alloca(size_t __size)
This temporary space is automatically freed when the function that called alloca() returns to its caller. Avr-libc defines the alloca() as a macro, which is translated into the inlined
__builtin_alloca()
function. The fact that the code
is inlined, means that it is impossible to take the address of this function, or to
change its behaviour by linking with a different library.