[cfe-dev] libcxx, libcxxabi, and runtime_error

[Richard Gorton]

Thank you for the quick response.  As an experiment, I did an svn export of both libcxx/libcxxabi from the current llvm project, and applied my porting changes to my local copy.
Unfortunately I still hit the same problem.  I did observe that I did have a: "#define LIBCXXRT 1" in my libcxx/include/__config for my architecture, which I think is incorrect (but I'm not clear about what impact it has).

I'll keep investigating, and report back with whatever I find.

Have others been able to do a libcxx/libcxxabi port to an architecture which does not already have a backing gcc+libs?

Regards,

	Richard Gorton


On May 27, 2014, at 10:42 AM, Marshall Clow <mclow.lists at gmail.com> wrote:

> 
> On May 27, 2014, at 6:09 AM, Richard Gorton <rcgorton at cognitive-electronics.com> wrote:
> 
>>> Hi - I'm trying to get C++ support for our architecture up and working (as a cross compiled environment) and I'm encountering some link errors:
>>> 
>>> build/lib/libc++.a(locale.cpp.o):(.data.rel.ro+0x2d0): undefined reference to `std::runtime_error::~runtime_error()'
>>> 
>>> 
>>> When I nm libcxx:locale.cpp.o, I see:
>>>               U _ZNSt13runtime_errorD1Ev
>>> 
>>> 
>>> In libcxxabi:stdexcept.o, I see:
>>> 0000000000000150 T _ZNSt13runtime_errorD0Ev
>>>               U _ZNSt13runtime_errorD1Ev
>>> 00000000000001f8 T _ZNSt13runtime_errorD2Ev
>>> 
>>> That is, in both cases, …runtime_errorD1Ev is undefined.
>>> 
>>> When I use c++filt to demangle the symbols listed in stdexcept.o, they all decode to
>>> 	std::runtime_error::~runtime_error()
>>> 
>>> 
>>> Any suggestions as to how to determine what is happening and why?
>>> 
>>> My setup: clang/llvm 3.3, with libcxx from the 3.3 release; libcxxabi is much more recent (6-May-2014, svn rev 208087)
> 
> I’m guessing that that’s your problem.
> ISTR that there was some migration of destructors between libc++ and libc++abi in the 3.3/3.4 time frame.
> (Though I would have expected multiple definitions, rather than no one defining it).
> 
> If you’re using libc++abi, then it should define the destructors for standard library exception classes.
> 
> — Marshall
>