strange output in c program

[Marko Turk]

On Wed, Jul 08, 2020 at 05:04:26PM +0530, rahul deshmukh wrote:
> Hi Team,
> i was learning c programming and came across a very strange output. kindly
> someone please guide me if i am missing anything.
> 
> rdx at FreeBSD:~/Projects/Clang/chapter3 % uname -a
> FreeBSD FreeBSD 12.1-RELEASE FreeBSD 12.1-RELEASE r354233 GENERIC  amd64
> ========================================================================
> rdx at FreeBSD:~/Projects/Clang/chapter3 % cat example6.c
> #include <stdio.h>
> int main()
> {
>     int a = 300, b, c;
>     if(a >= 400)
>     {
>         printf("shouldn't print\n");
>         b = 300;
>     }
>     c=200;
>     printf("%d %d\n", b, c);
>     return 0;
> }
> =========================================================
> rdx at FreeBSD:~/Projects/Clang/chapter3 % make example6
> `example6' is up to date.
> rdx at FreeBSD:~/Projects/Clang/chapter3 % ./example6
> 300 200==> should be garbage value instead of 300?

The behaviour is undefined so anything can happen. Even different
optimization flags can change the value printed.

BR/Marko
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