platform_build/Deprecation.md
Dan Willemsen c4bdff5f7e Mark the current BUILD_* warnings as errors by default
This switches:

  BUILD_COPY_HEADERS / LOCAL_COPY_HEADERS
  BUILD_HOST_EXECUTABLE
  BUILD_HOST_SHARED_LIBRARY
  BUILD_HOST_STATIC_LIBRARY

to errors by default. Devices can set
BUILD_BROKEN_USES_BUILD_HOST_EXECUTABLE (etc) to turn these errors back
to warnings. I've done that for all of our internal devices.

Bug: 130719878
Bug: 130696912
Bug: 130722971
Bug: 130723227
Test: remove the BUILD_BROKEN_USES_* lines from a device, see errors
Change-Id: I1aecf97f64e281df3682ff0a0fb3ac4283790acd
2020-02-19 18:11:18 -08:00

69 lines
3.4 KiB
Markdown

# Deprecation of Make
We've made significant progress converting AOSP from Make to Soong (Android.mk
to Android.bp), and we're ready to start turning off pieces of Make. If you
have any problems converting, please contact us via:
* The [android-building@googlegroups.com] group.
* Our [public bug tracker](https://issuetracker.google.com/issues/new?component=381517).
* Or privately through your existing contacts at Google.
## Status
[build/make/core/deprecation.mk] is the source of truth, but for easy browsing:
| Module type | State |
| -------------------------------- | --------- |
| `BUILD_AUX_EXECUTABLE` | Error |
| `BUILD_AUX_STATIC_LIBRARY` | Error |
| `BUILD_COPY_HEADERS` | Error |
| `BUILD_HOST_EXECUTABLE` | Error |
| `BUILD_HOST_FUZZ_TEST` | Error |
| `BUILD_HOST_NATIVE_TEST` | Error |
| `BUILD_HOST_SHARED_LIBRARY` | Error |
| `BUILD_HOST_SHARED_TEST_LIBRARY` | Error |
| `BUILD_HOST_STATIC_LIBRARY` | Error |
| `BUILD_HOST_STATIC_TEST_LIBRARY` | Error |
| `BUILD_HOST_TEST_CONFIG` | Error |
| `BUILD_NATIVE_BENCHMARK` | Error |
| `BUILD_SHARED_TEST_LIBRARY` | Error |
| `BUILD_STATIC_TEST_LIBRARY` | Error |
| `BUILD_TARGET_TEST_CONFIG` | Error |
| `BUILD_*` | Available |
## Module Type Deprecation Process
We'll be turning off `BUILD_*` module types as all of the users are removed
from AOSP (and Google's internal trees). The process will go something like
this, using `BUILD_PACKAGE` as an example:
* Prerequisite: all common users of `BUILD_PACKAGE` have been removed (some
device-specific ones may remain).
* `BUILD_PACKAGE` will be moved from `AVAILABLE_BUILD_MODULE_TYPES` to
`DEFAULT_WARNING_BUILD_MODULE_TYPES` in [build/make/core/deprecation.mk]. This
will make referring to `BUILD_PACKAGE` a warning.
* Any devices that still have warnings will have
`BUILD_BROKEN_USES_BUILD_PACKAGE := true` added to their `BoardConfig.mk`.
* `BUILD_PACKAGE` will be switched from `DEFAULT_WARNING_BUILD_MODULE_TYPES` to
`DEFAULT_ERROR_BUILD_MODULE_TYPES`, which will turn referring to
`BUILD_PACKAGE` into an error unless the device has overridden it.
* At some later point, after all devices in AOSP no longer set
`BUILD_BROKEN_USES_BUILD_PACKAGE`, `BUILD_PACKAGE` will be moved from
`DEFAULT_ERROR_BUILD_MODULE_TYPES` to `OBSOLETE_BUILD_MODULE_TYPES` and the
code will be removed. It will no longer be possible to use `BUILD_PACKAGE`.
In most cases, we expect module types to stay in the default warning state for
about two weeks before becoming an error by default. Then it will spend some
amount of time in the default error state before moving to obsolete -- we'll
try and keep that around for a while, but other development may cause those to
break, and the fix may to be to obsolete them. There is no expectation that the
`BUILD_BROKEN_USES_BUILD_*` workarounds will work in a future release, it's a
short-term workaround.
Just to be clear, the above process will happen on the AOSP master branch. So
if you're following Android releases, none of the deprecation steps will be in
Android Q, and the 2020 release will have jumped directly to the end for many
module types.
[android-building@googlegroups.com]: https://groups.google.com/forum/#!forum/android-building
[build/make/core/deprecation.mk]: /core/deprecation.mk