Errors when compiling C++ using cross GCC

[Mark G]

On Sun, Nov 20, 2016 at 1:09 PM, Florian Weimer <fw@deneb.enyo.de> wrote:
> I'd look at the output from “eu-readelf -s
> /opt/cross/lib/gcc/arm-linux-gnueabihf/6.2.0/../../../../arm-linux-gnueabihf/lib/libstdc++.so”

Hmm. Good idea. I looked at it with nm but not readelf. The output
looks similar to nm. For brevity:

$ eu-readelf -s
/opt/cross/lib/gcc/arm-linux-gnueabihf/6.2.0/../../../../arm-linux-gnueabihf/lib/libstdc++.so
|grep modfl
 3061: 001261d4    244 FUNC    WEAK   DEFAULT       11 modfl@@GLIBCXX_3.4.3
 5225: 000707b4      4 FUNC    GLOBAL DEFAULT       11 modfl@GLIBCXX_3.4.3
13894: 000707b4      4 FUNC    LOCAL  DEFAULT       11 __modfl_wrapper
13998: 001261d4    244 FUNC    LOCAL  DEFAULT       11 __modfl
17670: 001261d4    244 FUNC    WEAK   DEFAULT       11 modfl
19834: 000707b4      4 FUNC    GLOBAL DEFAULT       11 modfl@GLIBCXX_3.4.3

"modfl" is one of the duplicate symbols being reported.

> next.  It seems to me it contains a statically-linked copy of libm.a,
> which really should not happen.

I do think that is what's happening. I'm perplexed as to why it may be though.

> Since you are using a pre-built sysroot, maybe that's not set up for
> dynamic linking at all?

Nope. The pre-built sysroot most definitely supports dynamic linking
just fine. It's just a Debian ARM image with some configuration
tweaks.

Thanks,
Mark