llvm dev - Oct 2015 - [Windows Installer] Headerless install package?

Hello,

I've authored a tool based on clang's libtooling and wish to make its
build process similar to LLVM's via cmake on multiple platforms.

I'm primarily developing on Arch Linux (with the distribution-provided llvm)
and also maintain OS X builds using the prebuilt library archive from llvm.org.
The llvm packages for these platforms contain exactly what I expect: /lib,
/include, /bin, /share/cmake directories of everything from a default LLVM build
configuration.

When I shift my attention to Windows (building with VS) I'm unable to build
my tool with the official NSIS package of LLVM for two reasons:

- include exists, but only with (incomplete) C headers, no C++ headers at all
- no cmake package/modules whatsoever

Seemingly, the only use for the official NSIS package is the clang driver and
any tools that dynamically load the llvm/clang .dlls

I find this Windows deficiency rather odd, since the OS X package is complete
for tool developers. I've worked around this issue by building llvm/clang on
Windows myself and running CPack to produce a complete NSIS package (weighing in
at ~77MB).

Is there a motivation behind the stripping of this package against tool
developers? I'd like users to clone my tool source and build it quickly
without building llvm in its entirety.

This issue isn't critical, just a curiosity I have. 

Thanks!

-Jacko

Hi Jack,

On Sun, Oct 11, 2015 at 3:34 PM, Jack Andersen via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
> I've authored a tool based on clang's libtooling and wish to make
its build process similar to LLVM's via cmake on multiple platforms.
>
> I'm primarily developing on Arch Linux (with the distribution-provided
llvm) and also maintain OS X builds using the prebuilt library archive from
llvm.org. The llvm packages for these platforms contain exactly what I expect:
/lib, /include, /bin, /share/cmake directories of everything from a default LLVM
build configuration.
>
> When I shift my attention to Windows (building with VS) I'm unable to
build my tool with the official NSIS package of LLVM for two reasons:
>
> - include exists, but only with (incomplete) C headers, no C++ headers at
all
> - no cmake package/modules whatsoever
>
> Seemingly, the only use for the official NSIS package is the clang driver
and any tools that dynamically load the llvm/clang .dlls
>
> I find this Windows deficiency rather odd, since the OS X package is
complete for tool developers. I've worked around this issue by building
llvm/clang on Windows myself and running CPack to produce a complete NSIS
package (weighing in at ~77MB).
>
> Is there a motivation behind the stripping of this package against tool
developers? I'd like users to clone my tool source and build it quickly
without building llvm in its entirety.
The Windows installer (both the stable releases and weekly snapshots)
is targeted towards developers who wish to use Clang as a toolchain,
not as a library. The idea from the start was to optimize for early
adopters who wanted to try out clang-cl. The headers and libraries
aren't necessary for that, so we excluded them to keep binary size
down.

Besides the binary size issue, shipping the libraries in a useful way
is also tricky. We'd have to choose which msvcrt version to link with;
ideally it should match the one used by the library consumer.

This probably doesn't help you much, but that's the reasoning behind
the installer.

Cheers,
Hans

Thank you Hans,

Thought the CRT had something to do with it.

I've also discovered that mixing release/debug libraries is a major no-no
for the MSVC linker.

I sorta figured Windows would pose many challenges for a modular project, though
now I can properly explain that to my users.
> On Oct 12, 2015, at 11:33, Hans Wennborg <hans at chromium.org>
wrote:
> 
> Hi Jack,
> 
> On Sun, Oct 11, 2015 at 3:34 PM, Jack Andersen via llvm-dev
> <llvm-dev at lists.llvm.org> wrote:
>> I've authored a tool based on clang's libtooling and wish to
make its build process similar to LLVM's via cmake on multiple platforms.
>> 
>> I'm primarily developing on Arch Linux (with the
distribution-provided llvm) and also maintain OS X builds using the prebuilt
library archive from llvm.org. The llvm packages for these platforms contain
exactly what I expect: /lib, /include, /bin, /share/cmake directories of
everything from a default LLVM build configuration.
>> 
>> When I shift my attention to Windows (building with VS) I'm unable
to build my tool with the official NSIS package of LLVM for two reasons:
>> 
>> - include exists, but only with (incomplete) C headers, no C++ headers
at all
>> - no cmake package/modules whatsoever
>> 
>> Seemingly, the only use for the official NSIS package is the clang
driver and any tools that dynamically load the llvm/clang .dlls
>> 
>> I find this Windows deficiency rather odd, since the OS X package is
complete for tool developers. I've worked around this issue by building
llvm/clang on Windows myself and running CPack to produce a complete NSIS
package (weighing in at ~77MB).
>> 
>> Is there a motivation behind the stripping of this package against tool
developers? I'd like users to clone my tool source and build it quickly
without building llvm in its entirety.
> 
> The Windows installer (both the stable releases and weekly snapshots)
> is targeted towards developers who wish to use Clang as a toolchain,
> not as a library. The idea from the start was to optimize for early
> adopters who wanted to try out clang-cl. The headers and libraries
> aren't necessary for that, so we excluded them to keep binary size
> down.
> 
> Besides the binary size issue, shipping the libraries in a useful way
> is also tricky. We'd have to choose which msvcrt version to link with;
> ideally it should match the one used by the library consumer.
> 
> This probably doesn't help you much, but that's the reasoning
behind
> the installer.
> 
> Cheers,
> Hans