Switch everything to platforms
This patch switches the codebase over from using the "cpu"
mechanism to using bazel platforms. See
https://docs.bazel.build/versions/master/platforms.html for some more
information.
Most of the substantial changes are in //tools. Instead of using
`cc_toolchain_suite` rules, we now use regular `toolchain` rules that
are registered in the WORKSPACE. That also means that bazel now uses
the target platform to select the compiler.
All --cpu=* arguments should now be --config=* arguments. For example,
`--cpu=roborio` should now be `--config=roborio`. The CI script and
all documentation has been updated to reflect that.
The remainder of the changes revolve around tagging all targets with
`target_compatible_with`. The old mechanism allowed us to specify
repo-wide defaults. The new mechanism does not. That means every
target that didn't have any compatibility specified, now requires
compatibility with `@platforms//os:linux`.
I used buildozer for the vast majority of `target_compatible_with`
changes. buildozer automatically buildifies any BUILD files it
touches. That means this patch also contains a few non-functional
changes that I was too lazy to remove.
Change-Id: I66d6e6ad9161520ee397597cdb492585820a3acd
diff --git a/tools/platforms.bzl b/tools/platforms.bzl
new file mode 100644
index 0000000..fb2f69d
--- /dev/null
+++ b/tools/platforms.bzl
@@ -0,0 +1,11 @@
+load("@bazel_skylib//lib:selects.bzl", "selects")
+
+def _any_of(constraint_values):
+ return selects.with_or({
+ tuple(constraint_values): [],
+ "//conditions:default": ["@platforms//:incompatible"],
+ })
+
+platforms = struct(
+ any_of = _any_of,
+)