llvm dev - Aug 2010 - [LLVMdev] Linking to the LLVM shared library

The LLVM 2.7 release notes say you can use ./configure --enable-shared
to build LLVM as a shared library (libLLVM2.7.so), and the LLVM tools
will link against that instead of including the static libraries, so I
was wondering:

Is there a way to configure LLVM the same way using CMake (so it can
work on Windows)?

In the other direction, is there an equivalent ./configure flag to
setting CMake's LLVM_BUILD_TOOLS to "Off", like --disable-tools?

And is there a way to get llvm-config to output --libs/--ldflags that
will make third-party programs link dynamically instead of statically?
If there isn't a way, can that be added in 2.8? It'd be useful if
you're building more than one binary against LLVM and want to avoid
unnecessary file size bloat.

Thanks!

nobled <nobled at dreamwidth.org> writes:
> The LLVM 2.7 release notes say you can use ./configure --enable-shared
> to build LLVM as a shared library (libLLVM2.7.so), and the LLVM tools
> will link against that instead of including the static libraries, so I
> was wondering:
>
> Is there a way to configure LLVM the same way using CMake (so it can
> work on Windows)?
There is no way right now. It could be easily implemented for MinGW, but
not for MSVC. The binutils included with MinGW do not require
__declspec(dllexport/dllimport) for exporting/importing symbols on dlls.

[snip]

Óscar Fuentes <ofv at wanadoo.es> wrote:
> The following message is a courtesy copy of an article
> that has been posted to gmane.comp.compilers.llvm.devel as well.
>
> nobled <nobled at dreamwidth.org> writes:
>
>> The LLVM 2.7 release notes say you can use ./configure --enable-shared
>> to build LLVM as a shared library (libLLVM2.7.so), and the LLVM tools
>> will link against that instead of including the static libraries, so I
>> was wondering:
>>
>> Is there a way to configure LLVM the same way using CMake (so it can
>> work on Windows)?
>
> There is no way right now. It could be easily implemented for MinGW, but
> not for MSVC. The binutils included with MinGW do not require
> __declspec(dllexport/dllimport) for exporting/importing symbols on dlls.
>
> [snip]
Okay, but in the *general* case, how do I configure LLVM that way with
CMake (not necessarily on Windows)? running `cmake -i` never gives any
option that looks like "compile a shared library". Do the ./configure
and cmake ways of compiling not have parity, options-wise?

nobled <nobled at dreamwidth.org> writes:
>>> The LLVM 2.7 release notes say you can use ./configure
--enable-shared
>>> to build LLVM as a shared library (libLLVM2.7.so), and the LLVM
tools
>>> will link against that instead of including the static libraries,
so I
>>> was wondering:
>>>
>>> Is there a way to configure LLVM the same way using CMake (so it
can
>>> work on Windows)?
>>
>> There is no way right now. It could be easily implemented for MinGW,
but
>> not for MSVC. The binutils included with MinGW do not require
>> __declspec(dllexport/dllimport) for exporting/importing symbols on
dlls.
>>
>> [snip]
> Okay, but in the *general* case, how do I configure LLVM that way with
> CMake (not necessarily on Windows)? running `cmake -i` never gives any
> option that looks like "compile a shared library". Do the
./configure
> and cmake ways of compiling not have parity, options-wise?
No options-wise. Maybe some functionality-wise.

On cmake, when you want to generate shared libraries, you pass
-DBUILD_SHARED_LIBS That's a general cmake option, i.e. it should work
on all projects that use cmake (as far as they make sense for each
specific project.)

AFAIK, the `configure&make' build had so-so support for shared
libraries. Maybe that is fixed now. What they implemented recently was
one option for generating a single shared library containing all LLVM.