[Buildroot] [PATCH 1/1] protobuf: fix detection of __atomic_*() built-ins

[Carlos Santos <casantos@datacom.ind.br>]

[Thanks, Zimbra, for messing rearranging the messages in the inbox, so I answer them in the wrong order].

> From: "Thomas Petazzoni" <thomas.petazzoni@free-electrons.com>
> To: "Carlos Santos" <casantos@datacom.ind.br>
> Cc: buildroot at buildroot.org, "henrique marks" <henrique.marks@datacom.ind.br>
> Sent: Wednesday, February 10, 2016 1:50:37 PM
> Subject: Re: [PATCH 1/1] protobuf: fix detection of __atomic_*() built-ins

> Hello,
> 
> Thanks, this looks good, with one nit, see below.
> 
> On Wed, 10 Feb 2016 13:33:12 -0200, Carlos Santos wrote:
> 
>> diff --git
>> a/package/protobuf/0002-configure.ac-check-if-libatomic-is-needed.patch
>> b/package/protobuf/0002-configure.ac-check-if-libatomic-is-needed.patch
>> new file mode 100644
>> index 0000000..237bc71
>> --- /dev/null
>> +++ b/package/protobuf/0002-configure.ac-check-if-libatomic-is-needed.patch
>> @@ -0,0 +1,34 @@
>> +From 0883fa19d59ece19eec30937c65fd10162ef57b0 Mon Sep 17 00:00:00 2001
>> +From: Carlos Santos <casantos@datacom.ind.br>
>> +Date: Wed, 10 Feb 2016 12:54:43 -0200
>> +Subject: [PATCH] configure.ac: check if libatomic is needed
>> +
>> +In Buildroot, to simplify things, we've decided to simply require gcc 4.8
>> +as soon as the architectures has at least one __atomic_*() built-in
>> +variant that requires libatomic.
>> +
>> +Since protobuf most likely only uses the 1, 2 and 4-byte variants, it
>> +*could* technically build with gcc 4.7. This is probably not a big deal,
>> +and we can live with requiring gcc 4.8 on PowerPC to build protobuf.
>> +
>> +Signed-off-by: Carlos Santos <casantos@datacom.ind.br>
> 
> The patch description should not mention Buildroot and not mention
> Buildroot specific choices. It should be written as if you were going
> to submit it upstream, i.e with a proper justification as to why
> linking with libatomic may be needed.

This patch only exists to appease Buildroot but, anyway, I can rewrite the comment.

> And in fact, I'm even going to ask you to submit this patch upstream :-)

They don't need this. Their detection of the atomic built-ins already works without additional help.

Carlos Santos (Casantos)
DATACOM, P&D