初始化对象时,0是什么意思?

{0} 0

struct S { int a; char* b; int c; };
S ss = { 1, "asdf" };

ss.a 1 ss.b "asdf" ss.c int()

here

struct foo
{
    char c;
    int  i;
};

foo a = {0};

foo a;
memset(&a,0,sizeof(a));

SHELLEXECUTEINFO sexi = {};
char mytext[100] = {};

ShellExecuteEx() SHELLEXECUTEINFO

sexi.lpDirectory

SHELLEXECUTEINFO sexi = {0};

char mytext[100] = {0};

{0}

N1570 draft

0 0.0

{ }

int arr[2][2] = { { 1, 2 }, {3, 4} };

int arr[2][2] = { 1, 2, 3, 4 };

{ { 0 } }

some_type obj = { 0 };

obj

sexi.cbSize SHELLEXECUTEINFO { 0 }

memset

struct foo bar = { 0 };

struct f {
    int x;
    char a;
} my_zero_struct;

int main(void)
{
    return my_zero_struct.x;
}

gcc -O2 -o check check.c readelf -s check | sort -k 2

59: 0000000000601018     0 NOTYPE  GLOBAL DEFAULT  ABS __bss_start
48: 0000000000601018     0 NOTYPE  GLOBAL DEFAULT  ABS _edata
25: 0000000000601018     0 SECTION LOCAL  DEFAULT   25 
33: 0000000000601018     1 OBJECT  LOCAL  DEFAULT   25 completed.6531
34: 0000000000601020     8 OBJECT  LOCAL  DEFAULT   25 dtor_idx.6533
62: 0000000000601028     8 OBJECT  GLOBAL DEFAULT   25 my_zero_struct
57: 0000000000601030     0 NOTYPE  GLOBAL DEFAULT  ABS _end

my_zero_struct __bss_start main wikipedia on .bss

} my_zero_struct = { 0 };

.bss

memset