I'm trying to understand how the C Standard explains that the declaration can cause an error. Consider the following pretty simple code:
int main()
{
char test[1024 * 1024 * 1024];
test[0] = 0;
return 0;
}
This segfaluts. But the following code does not:
int main()
{
char test[1024 * 1024 * 1024];
return 0;
}
But when I compiled it on my machine the latest one segfaulted too. The main function looks as
00000000000008c6 <main>:
8c6: 55 push %rbp
8c7: 48 89 e5 mov %rsp,%rbp
8ca: 48 81 ec 20 00 00 40 sub $0x40000020,%rsp
8d1: 89 bd ec ff ff bf mov %edi,-0x40000014(%rbp) // <---HERE
8d7: 48 89 b5 e0 ff ff bf mov %rsi,-0x40000020(%rbp)
8de: 64 48 8b 04 25 28 00 mov %fs:0x28,%rax
8e5: 00 00
8e7: 48 89 45 f8 mov %rax,-0x8(%rbp)
8eb: 31 c0 xor %eax,%eax
8ed: b8 00 00 00 00 mov $0x0,%eax
8f2: 48 8b 55 f8 mov -0x8(%rbp),%rdx
8f6: 64 48 33 14 25 28 00 xor %fs:0x28,%rdx
8fd: 00 00
8ff: 74 05 je 906 <main+0x40>
901: e8 1a fe ff ff callq 720 <__stack_chk_fail@plt>
906: c9 leaveq
907: c3 retq
908: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1)
90f: 00
As far as I understood the segfault occurred when trying to mov %edi,-0x40000014(%rbp).
I tried to find the exaplanation in the N1570, Section 6.7.9 Initialization, but it does not seem to be the relevant one.
So how does the Standard explains this behavior?