[PATCH] D158709: [Headers][Modules] Make separate headers for the stdarg.h and stddef.h pieces so that they can be modularized

Fri Aug 25 08:54:55 PDT 2023

aaron.ballman added a reviewer: ChuanqiXu.
aaron.ballman added a comment.

I'm a bit concerned about the impact on (non-modules) build time performance. This splits stddef.h and stdarg.h into needing to open 14 different files instead of 2. Hopefully that's not a lot of overhead, but given that stddef.h is included in approximately every TU and that sometimes external forces cause files to be slow to open (network drives, AV software, etc), I think we should be cautious and measure the impact. I also really do not like how poorly this scales -- the fact that this is only needed for these two files helps a bit, but this is a lot of C++-specific hoops to jump through for C standard library headers.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D158709/new/

https://reviews.llvm.org/D158709