userbinator on What is C in practice?

MSVC will very confidently warn on cases like this by default:

    int foo() {
        int bar;
        return bar + 5; /* C4700: local variable 'bar' used without having been initialized */
    }

https://msdn.microsoft.com/en-us/library/axhfhh6x.aspx

In the same situation, GCC says "may be used uninitialized in this function" if you enable the warning (-Wmaybe-uninitialized), despite this being a trivial and certain case.

ydcvjk 11y

gcc 4.9.2 gives: warning: 'bar' is used uninitialized in this function

Maybe you are using a old version.

If you enable -Wall which you always should then this flag is automatically enabled.

https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#inde...

anon1385 11y

-Wuninitialized has been broken in GCC for over a decade: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=18501

anon4 11y

As if we needed more proof that GCC is a fucking joke...

ydcvjk 11y

Hey Linus, how are you doing!

bluecalm 11y

While I like MSVC team approach to this I don't think it's necessarily worse to just warn as long as that warning consistently work. I mean, just add some warning options to your compiling script and you are good to go. I am getting this error from GCC very consistently and as good as compilation error in practice.

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