| commit | 501b49a3ab4f0d099457b6e5b62c709a1d2311be | [log] [tgz] |
|---|---|---|
| author | Scott Graham <scottmg@chromium.org> | Wed Aug 05 13:03:37 2020 -0700 |
| committer | Commit Bot <commit-bot@chromium.org> | Mon Aug 10 18:49:02 2020 +0000 |
| tree | 6303562ae7f1953a23165f8f7b546b48d7fdc7d1 | |
| parent | 03df22eb2727dc732928fd0901c3a0cd46c689d7 [diff] |
clang: Add support for C++ modules in deps
This adds support for {{module_deps}}. This expansion is to be used by
the "cxx" tool. When the deps of a target include dependencies on
modules (defined as a target that includes a .modulemap file, which is
built to a .pcm), module_deps will be filled out with the required flags
to depend on those modules.
The targets that are depended upon must currently have a (handwritten)
.modulemap file in their sources.
The dependency semantics (as described in NinjaCBinaryTargetWriterTest)
are:
- .modulemap are built to .pcm by cxx_module
- .pcm aren't linked against
- The .cc of a target that uses modules depend on the .pcm ("implicit"
dependency in ninja terminology)
- The .cc sources of targets that depend on a module have implicit
dependencies on the pcm of the dependent modules target as well.
- A .a or executable does not depend on the .pcm.
Bug: fuchsia:27276
Change-Id: I84c26975b93db71e5309ad607fce900fe2705f90
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/9602
Commit-Queue: Scott Graham <scottmg@chromium.org>
Reviewed-by: Brett Wilson <brettw@chromium.org>
Reviewed-by: Petr Hosek <phosek@google.com>
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