Type cast doesn't work in ternary operator

[Vincent Lefevre]

On 2015-03-02 01:16:40 -0700, wangwzc wrote:
> The code is as following, when I change the Line15 to (*((struct b_t
> *)(&dst)) = *((struct b_t *)(&src))) , or I change the Line16 to (*((struct
> a_t *)(&dst)) = *((struct a_t *)(&src))), it's OK. Quite strange, why two
> kind of type cast doesn't work.

Line 16 is already (*((struct a_t *)(&dst)) = *((struct a_t *)(&src))).

> # gcc a.c
> a.c: In function `main':
> a.c:15: error: type mismatch in conditional expression
> 
> ========== a.c =============
> struct a_t {
> 	int		sa_family;
> };
> 
> struct b_t {
> 	int 	sa_family;
> };
> 
> int main()
> {
> 	struct b_t dst, src;
> 
> 	(src.sa_family == 1) ?
> 	(*((struct a_t *)(&dst)) = *((struct a_t *)(&src))) :	
> 	(*((struct a_t *)(&dst)) = *((struct a_t *)(&src)));
> 
> 	return 0;
> }

No problems with GCC 4.9.2.

Note that struct a_t and struct b_t are not compatible, even though
they look the same.

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Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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