[cfe-dev] Improving PCH build times by instantiating templates in the PCH

[Lubos Lunak via cfe-dev]

 Hello,

 would there be somebody who could review https://reviews.llvm.org/D69585 so 
that it can make it into 10.0? I can get significant build time reduction 
with the patch when using PCHs (up to 20-30% build time, 
http://llunak.blogspot.com/2019/11/clang-precompiled-headers-and-improving.html), 
the patch is fairly simple, I've been using it locally for several months by 
now, and it should be pretty safe given that the change is in effect only if 
opted in.

 Thank you.

-- 
 Lubos Lunak