Re: [PATCH] fix a code style in drivers/char/virtio_console.c

From: Amit Shah
Date: Tue May 18 2010 - 02:31:08 EST


Hello,

On (Tue) May 18 2010 [13:41:29], Steven Liu wrote:
> Hi, Amit,
>
> if 'err' initialised in this path, it needn't do err = -ENOMEM
> after,isn't it?

What I mean is if we later add some code that just does:

if (err)
goto fail;

then 'ret' can be -ENOMEM, as it was initialised to, which would be
fine. But if a later patch adds something like:

+ ret = -EIO;
+ err = ...
+ if (err)
+ goto fail;
+
err = ...
if (err)
goto fail;

In this case, the 2nd if() would now return EIO instead of ENOMEM as
earlier.

Also, this style of coding can prevent uninitialised usage of 'ret', eg:


int ret;

if (err)
goto fail;

fail:
return ret;

In this case, the compiler will warn about 'ret' being used
uninitialised.

This is just a coding style issue. I had initially coded it the way your
patch does, but Rusty asked me to change that and I like this new style
better: there's less scope for surprises.

Amit
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