Somebody wrote the following C program and asked why gcc allows "to change the base address of an array". He was aware that the code is terrible but still wanted to know. I found the question interesting enough, because the relationship between arrays and pointers in C is subtle (behold the use of the address operator on the array! "Why would anybody do that?"), confusing and consequently often misunderstood. The question was deleted but I thought I ask it again, with proper context and — as I hope — a proper answer to go with it. Here is the original prog.
static char* abc = "kj";void fn(char**s){ *s = abc;}int main() { char str[256]; fn(&str);}It compiles with gcc (with warnings), links and runs. What happens here? Can we change the base address of an array by taking its address, casting it to pointer to pointer (after all arrays are almost pointers in C, aren't they) and assigning to it?
