RE: git on HP NonStop

From: Johannes Sixt [mailto:j.sixt@viscovery.net]
Sent: Monday, August 20, 2012 12:57 PM
To: Joachim Schmitz
Cc: 'Jan Engelhardt'; 'Junio C Hamano'; git@vger.kernel.org
Subject: Re: git on HP NonStop

Am 8/20/2012 12:36, schrieb Joachim Schmitz:

quoted

int var = var;
char *othervar = othervar;

...

What is the reason for using that self-init stuff? I don't think it is
really portable, is it?

It is used to avoid "var may be used uninitialized" warnings for some

compilers.

Well, it results in a similar warning on NonStop. "var is used before it is
set" and I think this is equally bad.
In either case we don't know what the content of that var is.

E.g. in wt_status.c the variable 'status' is set at only one place, but
later it is switched on. If lucky we get to the default case and die.
So why not just 
int status = 0;

Officially (according to the C standard), it is undefined behavior. 

Yes, I had that suspicion. Not good to rely in this...

But I've observed considerable resistance by Junio to fix this properly. 

What's the  reason behind that?

Therefore, unless
you can show that your compiler generates unusable code you better live

with

the "self-initialization" warnings.

So far I can't, so I guess I'll have to live with the warnings, but don't
quite like it.
 

-- Hannes

Bye, Jojo