在 C 中，!0 总是 return 1 吗？

Question

这个程序有趣地表明 ! 0 的整数值为 1:

#include <stdio.h>

int main( int argc, char* argv[] ) {
  printf( "%d\n", ! 0 );
  return 0;
}

$ gcc --version && gcc -g ./main.c && ./a.out
gcc (Debian 6.3.0-18+deb9u1) 6.3.0 20170516
Copyright (C) 2016 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

1
$

这是否有任何标准保证，或者 ! 0 是否可以评估任何其他非零整数值？

Answer 1

保证计算结果为 1。

6.5.3.3 Unary arithmetic operators
...
5 The result of the logical negation operator ! is 0 if the value of its operand compares unequal to 0, 1 if the value of its operand compares equal to 0. The result has type int. The expression !E is equivalent to (0==E).

^{C 2011 Online Draft}

在 C 中，!0 总是 return 1 吗？

In C, will !0 always return 1?

c

integer

zero