Re: [Qemu-devel] [PATCH v2 52/60] json: Eliminate lexer state IN_WHITESPACE, pseudo-token JSON_SKIP

[Eric Blake]

On 08/20/2018 06:51 AM, Markus Armbruster wrote:

> > Hmm, if we did this:
> >
> > [IN_START_INTERPOL] {
> >    ['%'] = IN_INTERPOL,
> >    ['\t'] = IN_START_INTERPOL,
> > ...
> > }
> >
> > for similarity with all our other constructs, will gcc remember that
> > we've already initialized other members not listed in the clause
> > before, or will it mistakenly re-0-initialize the array members not
> > mentioned?
>
> Fails make check.
>
> (gdb) p json_lexer[IN_START_INTERPOL]
> $1 = "\000\000\000\000\000\000\000\000\000\016\016\000\000\016", '\000' <repeats 18 times>, 
> "\016\000\000\000\000\035", '\000' <repeats 217 times>

And thus answered my question - abbreviating causes gcc to 
re-zero-initialize any unmentioned members, so your override has to be 
one member at a time, as originally written.

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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