What is modularize

Modularize is a tool named after clang's modularize tool to allow you to modularize a platform.

How do I use it?

If you want to create a new platform, you will want to do the following. If you want to update an existing platform, you can either follow the instructions below, or replace the -C <directory> with --all to update all platforms (strongly recommended to do this at least once before submitting).

1. Create a gn output directory for said platform with the following values set:
   • target_os = "<platform's os>"
   • target_cpu = "<platform's cpu>"
   • use_clang_modules = true (required because of libcxx's generated directories)
2. Run modularize.py -C out/<directory> --cache (--cache is strongly recommended, --no-cache should only be used if you've modified compiler.py or modulemap.py. Caching reduces the runtime from minutes to ~1 second).
3. Check if it works (don't forget to set use_autogenerated_modules = true in your args.gn)
4. If it doesn't work, you can modify config.py to add any customization, then go back to step 2.

For example, if you want to create a linux-arm64 configuration, you would create or reuse an output directory with the following args.gn:

target_os = "linux"
target_cpu = "arm64"
use_clang_modules = true