From mboxrd@z Thu Jan  1 00:00:00 1970
MIME-Version: 1.0
In-Reply-To: <af298c734424023e1fe904f7bb0708c2@terzarima.net>
References: <dd6fe68a1002061606r4f58ec17g19d037cc8265303@mail.gmail.com>
	 <af298c734424023e1fe904f7bb0708c2@terzarima.net>
Date: Sun,  7 Feb 2010 12:01:16 -0800
Message-ID: <dd6fe68a1002071201n42094728o7f41d7e23faa24d7@mail.gmail.com>
Subject: Re: [9fans] NaN, +Inf, and -Inf, constants?
From: Russ Cox <rsc@swtch.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Content-Type: multipart/alternative; boundary=000e0cd2dc62b68026047f08252a
Topicbox-Message-UUID: cfde25c6-ead5-11e9-9d60-3106f5b1d025

--000e0cd2dc62b68026047f08252a
Content-Type: text/plain; charset=UTF-8

On Sun, Feb 7, 2010 at 2:46 AM, Charles Forsyth <forsyth@terzarima.net>wrote:

> h% cat en.c
> enum{
>        Fred= 1.5
> };
> double f = Fred;
> h% 8c -S en.c
>        DATA    f+0(SB)/8,$(1.50000000000000000e+00)
>        GLOBL   f+0(SB),$8
>        END     ,
>
> bug or quirk?
> what do you think?
>

i swear i tested this before i replied...

seems like a bug to me.  the spec is pretty clear:

       6.7.2.2  Enumeration specifiers

       Syntax

       [#1]

               enum-specifier:
                       enum identifier-opt { enumerator-list }
                       enum identifier-opt { enumerator-list , }
                       enum identifier

               enumerator-list:
                       enumerator
                       enumerator-list , enumerator

               enumerator:
                       enumeration-constant
                       enumeration-constant = constant-expression

       Constraints

       [#2] The expression that defines the value of an enumeration
       constant shall be an integer constant expression that has  a
       value representable as an int.

russ

--000e0cd2dc62b68026047f08252a
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

On Sun, Feb 7, 2010 at 2:46 AM, Charles Forsyth <span dir=3D"ltr">&lt;<a hr=
ef=3D"mailto:forsyth@terzarima.net">forsyth@terzarima.net</a>&gt;</span> wr=
ote:<br><div class=3D"gmail_quote"><blockquote class=3D"gmail_quote" style=
=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
h% cat en.c<br>
enum{<br>
 =C2=A0 =C2=A0 =C2=A0 =C2=A0Fred=3D 1.5<br>
};<br>
double f =3D Fred;<br>
h% 8c -S en.c<br>
 =C2=A0 =C2=A0 =C2=A0 =C2=A0DATA =C2=A0 =C2=A0f+0(SB)/8,$(1.500000000000000=
00e+00)<br>
 =C2=A0 =C2=A0 =C2=A0 =C2=A0GLOBL =C2=A0 f+0(SB),$8<br>
 =C2=A0 =C2=A0 =C2=A0 =C2=A0END =C2=A0 =C2=A0 ,<br>
<br>
bug or quirk?<br>
what do you think?<br></blockquote><div><br></div><div>i swear i tested thi=
s before i replied...</div></div><br><div>seems like a bug to me. =C2=A0the=
 spec is pretty clear:</div><div><br></div><div><div>=C2=A0=C2=A0 =C2=A0 =
=C2=A0 6.7.2.2 =C2=A0Enumeration specifiers</div>
<div><br></div><div>=C2=A0=C2=A0 =C2=A0 =C2=A0 Syntax</div><div><br></div><=
div>=C2=A0=C2=A0 =C2=A0 =C2=A0 [#1]</div><div><br></div><div>=C2=A0=C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 enum-specifier:</div><div>=C2=A0=
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 enum identifier-opt { enumerator-list }</div><div>=C2=A0=C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 enum identif=
ier-opt { enumerator-list , }</div>
<div>=C2=A0=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 enum identifier</div><div><br></div><div>=C2=A0=C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 enumerator-list:</div><div>=C2=A0=C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 enume=
rator</div><div>=C2=A0=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 enumerator-list , enumerator</div><div><br>
</div><div>=C2=A0=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 enumerato=
r:</div><div>=C2=A0=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 enumeration-constant</div><div>=C2=A0=C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 enumeration-con=
stant =3D constant-expression</div><div><br></div><div>=C2=A0=C2=A0 =C2=A0 =
=C2=A0 Constraints</div><div>
<br></div><div>=C2=A0=C2=A0 =C2=A0 =C2=A0 [#2] The expression that defines =
the value of an enumeration</div><div>=C2=A0=C2=A0 =C2=A0 =C2=A0 constant s=
hall be an integer constant expression that has =C2=A0a</div><div>=C2=A0=C2=
=A0 =C2=A0 =C2=A0 value representable as an int.</div><div><br>
</div><div>russ</div></div>

--000e0cd2dc62b68026047f08252a--