[Buildroot] [autobuild.buildroot.net] Build results for 2016-02-27

[Arnout Vandecappelle]

On 02/28/16 16:44, Jörg Krause wrote:
> On So, 2016-02-28 at 16:06 +0100, Arnout Vandecappelle wrote:
>> On 02/28/16 12:17, Jörg Krause wrote:
>>>
>>> On So, 2016-02-28 at 10:42 +0100, Peter Korsgaard wrote:
>>>>>>>>> "Jörg" == Jörg Krause <joerg.krause at embedded.rocks>
>>>>>>>>> writes:
>>>>  > On So, 2016-02-28 at 08:30 +0100, Thomas Petazzoni wrote:
>>>>  >>  
>>>>  >>      powerpc |                    czmq-v3.0.2 | NOK |
>>>>  >> http://autobuild.buildroot.net/results/2061238affb685db998100a56c6571538d089a5b/
>>>>
>>>>  > /home/test/autobuild/instance-3/output/host/usr/powerpc-buildroot-linux-uclibc/sysroot/usr/lib/libstdc++.a(compatibility-ldbl.o): In function `std::tr1::hash<long double>::operator()(long double) const':
>>>>  > compatibility-ldbl.cc:(.text._ZNKSt3tr14hashIeEclEe+0x3c): undefined reference to `frexpl'
>>>>
>>>>  > I cannot reproduce it on my 64-bit host.
[snip]
> That's why I sent a patch with LIBS=-lm.

 The problem turns out to be more complicated... It's actually a problem with
libstdc++. Dependeing on the arch, some functions will be in
compatibility-ldbl.o. If you use any of these functions, that file will be
linked in. And when that file is linked in, all the _other_ functions, which you
actually don't use, are also linked in. And one of these functions is the
template function hash<long double>::operator(), which uses frexpl.

 So, requiring czmq to link with -lm is a bit weird, given that neither itself,
nor any of its dependencies really need it...

 So ideally it should be fixed in libstdc++ itself. But I have no idea how to do
that...

 Regards,
 Arnout

-- 
Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium           BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
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