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From: Kyohei Kadota <lufia@lufia.org>
Date: Wed,  3 Apr 2019 00:16:28 +0900
Message-ID: <CAFMepckUx1aMg48iw=eBXiVkxg_BvnbjqQqT9OVLTdhd=eSxaQ@mail.gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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Subject: Re: [9fans] Don't Plan 9 C compiler initialize the rest of member
 of a struct?
Topicbox-Message-UUID: f85aa12e-ead9-11e9-9d60-3106f5b1d025

I see, I understand. thank you, Skip, Charles.

2019=E5=B9=B44=E6=9C=883=E6=97=A5(=E6=B0=B4) 0:06 Charles Forsyth <charles.=
forsyth@gmail.com>:
>
>
>> What is "be initialized implicitly the same as objects that have
>> static storage duration" mean?
>
>
> It refers back to the second part of case 10 of that section.
>
> On Tue, 2 Apr 2019 at 15:53, Kyohei Kadota <lufia@lufia.org> wrote:
>>
>> Thank you for a reply.
>>
>> I read spec on http://www.open-std.org/jtc1/sc22/WG14/www/docs/n1256.pdf
>> then I'm confusing.
>> This spec describes Initialization:
>>
>> > 6.7.8 Initialization, p127
>> >
>> > 19 The initialization shall occur in initializer list order, each init=
ializer provided for a
>> > particular subobject overriding any previously listed initializer for =
the same subobject;132)
>> > all subobjects that are not initialized explicitly shall be initialize=
d implicitly the same as
>> > objects that have static storage duration.
>>
>> What is "be initialized implicitly the same as objects that have
>> static storage duration" mean?
>>
>> 2019=E5=B9=B44=E6=9C=882=E6=97=A5(=E7=81=AB) 9:27 Jeremy O'Brien <neutra=
l@fastmail.com>:
>> >
>> > On Mon, Apr 1, 2019, at 11:33, Kyohei Kadota wrote:
>> > > Hi, 9fans. I use 9legacy.
>> > >
>> > > About below program, I expected that flags field will initialize to
>> > > zero but the value of flags was a garbage, ex, "f8f7".
>> > > Is this expected?
>> > >
>> > > ```
>> > > #include <stdio.h>
>> > >
>> > > struct option {
>> > >     int n;
>> > >     char *s;
>> > >     int flags;
>> > > };
>> > >
>> > > int
>> > > main(void)
>> > > {
>> > >     struct option opt =3D {1, "test"};
>> > >     printf("%d %s %x\n", opt.n, opt.s, opt.flags);
>> > >     return 0;
>> > > }
>> > > ```
>> > >
>> > >
>> >
>> > According to C99: "If an object that has automatic storage duration is=
 not initialized explicitly, its value is indeterminate."
>> >
>> > Stack variable =3D=3D automatic storage duration. This appears to be c=
orrect behavior to me.
>> >
>>