Thread: BuYS:Compiler magic!

Originally Posted by sebas_phoenix

Hey guys,

Long time...Hope you are all doing well.. I made a small programming puzzle @ The compiler magic! « phr33dom

Try solving it. And FYI , kindly post the answers as comments in the blog coz i have asked the same puzzle elsewhere too and it might be useful to a larger audience which includes my college juniors as well . And yeah, it is not a trick to generate blog traffic If you feel, PM me the solutions too , i leave it up to u to submit the solutions the way you prefer.

Got a lot of catching up to do in g4h..

Till then ,

Peace

Heheh .. we would never see it as a "trick to generate blog traffic" . Keep posting man !

Haha, i know dude.. Just kidding...

Namaste

The compilers check for a return statement and it is present but it is present (otherwise logically compilation should generate a warning).

Now the answer is:
The function is typecasted to int, it should return an int and return values are prepared into eax register.

This is the case with return line; now with else statement:

res=num*fact(num-1);

the res variable is might also be going inside EAX register right before the natural ending of the function i.e. the epilogue.

And thats why due to in both cases the EAX register is getting the value, thats why this code is working correctly.

Note: haven't checked the compiled/dissembled code, but a blind guess depending on the most of compiler's behavior.

..."vinnu"

Posted the answer @ The compiler magic! « phr33dom

@Vinnu bro: the 'res' variable will go into eax, if there was an 'explicit' return statement.