Re: [boost] clang-win, again

Subject: Re: [boost] clang-win, again
From: degski (degski_at_[hidden])
Date: 2018-10-31 06:45:57

On Tue, 30 Oct 2018 at 17:18, Peter Dimov via Boost <boost_at_[hidden]>
wrote:

> > If you are able to build all, correctly, ...
>
> I can, but I don't use lld or thin-lto.
>

You should try ThinLTO
<http://blog.llvm.org/2016/06/thinlto-scalable-and-incremental-lto.html>,
it can generate wildly better binary code [and Clang/llvm does not
implement VC's LTO]. For being able to benefit, you'll need lld
<https://clang.llvm.org/docs/ThinLTO.html>, though.

That's a bit odd because clang-win is basically clang-cl.exe, which is the
> cl.exe-compatible driver, and you'll be trying to use decidedly non-cl.exe
> things.
>

As you can spot in the docs <https://clang.llvm.org/docs/ThinLTO.html> ,
clang-cl is specifically mentioned in relation to ThinLTO and lld.

But you can try with your config, I suppose. Use
>
> <archiver>"\"C:\\Program Files\\LLVM\\llvm-ar.exe\""
>
> for now, to manually quote it.
>

I'll try that.

--target, <architecture>, <address-model> shouldn't be needed.
>

How do I get 64-bit binaries then?

As Edward pointed out at length, clang, clang-cl and clang++ are the same
binary. You can pass gcc-like options "through" clang-cl, using the -Xclang
prefix, f.e. '-Xclang -fforce-enable-int128', will make gcc-style 128-bit
ints available on Windows (targeting VC, to keep the ED-speak).

degski
-- 
*“If something cannot go on forever, it will stop" - Herbert Stein*