Seg fault, bug in gcc compiler??

[achillez]

#include <stdio.h>

int main() {
        unsigned short i = 0;
        scanf("%u", &i);
        printf("%u", i);
}
/*
int main() {
        unsigned short i = 0, j = 0;
        scanf("%u", &i);
        printf("%u", i);
}
*/

hey try the above prog, cc short.c -o short
then ./short
enter a number, you ll end up in seg fault.

you can comment the first n try d second main(), it works fine.
what is wrong? is it wid my code? or is it wid d compiler? or is it somewhr else?

Thanx for checkin on it.!

[achillez]

well, guys it works fine in VC++. but not wid GCC. Y is it??

[Salem]

Nothing wrong with the compiler, just bugs in your code.

$ gcc -W -Wall -ansi -pedantic -O2 foo.c
foo.c: In function `main':
foo.c:5: warning: unsigned int format, different type arg (arg 2)
foo.c:7: warning: control reaches end of non-void function

If you fixed the scanf format to be correct for an unsigned short, then it would work properly.

Your second program only works because the memory trashed by %u is the 'j' variable, and not something critically important to the running of the program.

> guys it works fine in VC++. but not wid GCC. Y is it??
That's just dumb luck on your part, nothing more.

Think of it in terms of running across a minefield. Just because you fail to cause an explosion, do you immediately conclude there are no mines?

http://www.catb.org/~esr/faqs/smart-questions.html#writewell
http://www.catb.org/~esr/faqs/smart-questions.html#id306617

[achillez]

hi,

thanx for telling me wats wrong.

gcc -W -Wall -ansi -pedantic -O2 foo.c

why do i have to use this to compile tat prog? ow do u do it otherwise?

n abt tat mine stuff, well i was askin if it was wrong wid compiler, i dint conclude its wrong wid gcc. may be i was being over optimistic wid it. now i know, i know nothin in c.

[VernonDozier]

He added those compile tags to list the warnings. Without them it compiles, but doesn't list them. He has a good point about "abt", "tat", etc. when he listed the link. It's hard to take your question seriously when you write like that.

[achillez]

Okay boss!

[Belrog]

You really should read http://www.catb.org/~esr/faqs/smart-...html#writewell

As WaltP put it "At least use English. ... Unless your name is Stepin Fetchit."