On Wed, 06 Oct 2010 16:20:41 +0400, Manuel König <manuel...@gmx.net> wrote:
Hi,
did anyone have success using the llvm-2.7 D-bindings from the bindings
project http://www.dsource.org/projects/bindings on x86_64 linux? I
tried so far with ldc, but the compiler chokes about a mere 3570 lines
of unresolved symbols when linking with ldc, compiling works fine.
Short version:
==============
I think the question boils down to "How do I create a D library and
link it into a c++ program on x86_64 linux using ldc (or gdc or
<any_other_D_compiler>)".
Long version:
=============
Here's a snip of the linker error messages I get from ldc:
// -- file main.d
import llvm.c.Core;
void main()
{
auto context = LLVMGetGlobalContext();
}
// --
$ ldc -I=/path/to/llvm-2.7 \
-L=/usr/local/lib/libLLVM{Core,Support,System}.a main.d
/usr/local/lib/libLLVMCore.a(Core.o): In function `LLVMContextCreate':
Core.cpp:(.text+0x57): undefined reference to `operator new(unsigned
long)'
/usr/local/lib/libLLVMCore.a(Core.o): In function
`LLVMModuleCreateWithName':
Core.cpp:(.text+0x13a): undefined reference to `operator new(unsigned
long)'
/usr/local/lib/libLLVMCore.a(Core.o): In function
`LLVMModuleCreateWithNameInContext':
Core.cpp:(.text+0x195): undefined reference to `operator new(unsigned
long)'
/usr/local/lib/libLLVMCore.a(Core.o): In function `LLVMSetDataLayout':
Core.cpp:(.text+0x240): undefined reference to `std::basic_string<char,
std::char_traits<char>, std::allocator<char> >::basic_string(char
const*, unsigned long, std::allocator<char> const&)'
Core.cpp:(.text+0x24f): undefined reference to `std::basic_string<char,
std::char_traits<char>, std::allocator<char>
::assign(std::basic_string<char, std::char_traits<char>,
std::allocator<char> > const&)'
Core.cpp:(.text+0x25e): undefined reference to `std::basic_string<char,
std::char_traits<char>, std::allocator<char>
::_Rep::_S_empty_rep_storage'
Core.cpp:(.text+0x294): undefined reference to `std::basic_string<char,
std::char_traits<char>, std::allocator<char>
::_Rep::_M_destroy(std::allocator<char> const&)'
[...]
After scanning over the error messages, I think it's only operator,
delete and std::* symbols that are missing. I also get the same error
messages when I try to compile an equivalent C program that uses the
llvm-c/* headers with gcc, but it works with g++, so I'm quite sure the
problem is the missing c++ runtime, which is nonexistent in ldc.
I think there are only two ways to solve this:
(1) link the c++ runtime to ldc (I have no clue how to do that or if
it's possible)
(2) Write a D library using the llvm D-bindings, define a semi-main
function as extern(C), and write a c++ wrapper program that links
to the D library and does nothing more than calling the semi-main
function. The llvm symbols and c++ runtime will then be linked in
using g++.
Option (2) seems easy, but ldc does not seem to have a linker swith to
build libraries, and doing
ldc -c myprog.d # produces myprog.o
ar -cq myprog.a myprog.o
to generate a library from the object file doesn't work because there
are still undefined symbols to the main function or the module ctors
in there, even when myprog.d doesn't define a main function. I could
try to hack those missing functions back in by defining them in the C
program, but there must be some simpler way to generate libraries,
or am I at a loosing front here?
I also consider using other compilers than ldc as an option, but afaik
the only other usable compiler might be gdc (is that stable by now?).
You should probably ask LDC guys (irc://irc.freenode.net/ldc)
