tree bfd15e960089a197dccca0852b17c259d73cf1e4
parent a156d0b1306b09bf676a72e345ca978ef6093d95
author Matt Stark <msta@google.com> 1762235802 +1100
committer GN LUCI <gn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1763941228 -0800

Make clang modules output -fmodule-file=foo=<pcm>.

-fmodule-file=<pcm> is deprecated, and it also reads the module files
eagerly instead of lazily.

This decreases the compile times of an empty file for chrome from 60ms
to 30ms.

https://clang.llvm.org/docs/StandardCPlusPlusModules.html#specifying-bmi-dependencies
Change-Id: Iac7e4d86c79f75fa4e58c0e9b75f46216a6a6964
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/20380
Commit-Queue: Matt Stark <msta@google.com>
Reviewed-by: Takuto Ikuta <tikuta@google.com>