From: Eitan Adler <lists@eitanadler.com>
To: Peter Stephenson <p.stephenson@samsung.com>
Cc: Zsh hackers list <zsh-workers@zsh.org>
Subject: Re: [PATCH 2/2] Fix two C nits
Date: Mon, 18 Jun 2018 22:31:43 -0700 [thread overview]
Message-ID: <CAF6rxg=A1qEdR7waJBs04jXePfgTc-nV2_JXigA_rO6FMtzsrg@mail.gmail.com> (raw)
In-Reply-To: <20180618092243eucas1p133cc109ed17712cd4253a72da472fa54~5NsPXgtMr0676306763eucas1p1g@eucas1p1.samsung.com>
On 18 June 2018 at 02:22, Peter Stephenson <p.stephenson@samsung.com> wrote:
> On Sat, 16 Jun 2018 01:04:27 +0000
> Eitan Adler <lists@eitanadler.com> wrote:
>> - avoid returning from a function that will never return
>>
>> diff --git a/Src/exec.c b/Src/exec.c
>> index d44527841..b36bcef64 100644
>> --- a/Src/exec.c
>> +++ b/Src/exec.c
>> @@ -4954,7 +4954,6 @@ getpipe(char *cmd, int nullexec)
>> execode(prog, 0, 1, out ? "outsubst" : "insubst");
>> cmdpop();
>> _exit(lastval);
>> - return 0;
>> }
>
> I'm not 100% sure about this since you're relying on the compiler
> knowing that _exit won't return. Probably the majority of compilers
> we're involved with for zsh will work that out, but I'm not sure
> it's actually required by the C standard that they know the function
> doesn't return, is it? You may know some corner I haven't investigated.
It is only required that any function either return, exit, or loop
forever [0]. While I don't much about non-modern compilers, it
shouldn't affect anything to remove the return. At best, it'll do
nothing. At worst older compilers might incorrectly issue a
diagnostic. IMHO we should defer to modern compilers when it comes to
diagnostics provided the more esoteric options still work.
> I'd have been tempted to add /*NOTREACHED*/ on the next line.
[0] there is some interesting ancient nuance here, but it's not
important for this discussion.
--
Eitan Adler
next prev parent reply other threads:[~2018-06-19 5:32 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20180616021439epcas4p327f4346b40d9e10d94ce055058fe0d71@epcas4p3.samsung.com>
2018-06-16 1:04 ` Eitan Adler
2018-06-18 9:22 ` Peter Stephenson
2018-06-19 5:31 ` Eitan Adler [this message]
2018-06-19 13:46 ` Vincent Lefevre
2018-06-19 14:13 ` Peter Stephenson
2018-06-19 14:38 ` Vincent Lefevre
2018-06-19 15:59 ` Peter Stephenson
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