Our SVG code depends on our XML code which depends on expat.
See also cl/457481999
Change-Id: I83b61f5d73570d0aa7e851a01ccd019b4b1019e4
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/553376
Reviewed-by: Florin Malita <fmalita@google.com>
The big change here is having the C++ toolchain use
Bazel platforms instead of the C++ specific flags/setup.
In Bazel, platforms are a general purpose way to define
things like os, cpu architecture, etc. We were not using
platforms previously, because the best documentation at
the time focused on the old ways.
However, the old ways were clumsy/difficult when trying
to manage cross-compilation, specifically when trying
to have a Mac host trigger a build on our Linux RBE
system targeting a Linux x64 system. Thus, rather than
keep investing in the legacy system, this CL migrates
us to using platforms where possible.
Suggested background reading to better understand this CL:
- https://bazel.build/concepts/platforms-intro
- https://bazel.build/docs/platforms
- https://bazel.build/docs/toolchains#registering-building-toolchains
The hermetic toolchain itself is not changing in this CL
(and likely does not need to), only how we tell Bazel
about it (i.e. registering it) and how Bazel decides
to use it (i.e. resolving toolchains).
Here is my understanding of how platforms and toolchains
interact (supported by some evidence from [1][2])
- Bazel needs to resolve platforms for the Host, Execution,
and Target.
- If not specified via flags, these are the machine from
which Bazel is invoked, aka "@local_config_platform//:host".
- With this CL, the Host could be a Mac laptop, the Execution
platform is our Linux RBE pool, and the Target is "a Linux
system with a x64 CPU"
- To specify the Host, that is, describe to Bazel the
capabilities of the system it is running on, one can
set --host_platform [3] with a label pointing to a platform()
containing the appropriate settings. Tip: have this
platform inherit from @local_config_platform//:host
so it can add to any of the constraint_settings and
constraint_values that Bazel deduces automatically.
- To specify the Target platform(s), that is, the system
on which a final output resides and can execute, one
can set the --platforms flag with a label referencing
a platform().
- Bazel will then choose an execution platform to fulfill
that request. Bazel will look through a list of available
platforms, which can be augmented* with the
--extra_execution_platforms. Platforms specified by this
flag will be considered higher than the default platforms!
- Having selected the appropriate platforms, Bazel now
needs to select a toolchain to actually run the actions
of the appropriate type.
- Bazel looks through the list of available toolchains
and finds one that "matches" the Execution and the Target
platform. This means, the toolchain's exec_compatible_with
is a strict subset of the Execution platform and
the toolchain's target_compatible_with is a strict subset
of the Target platform. To register toolchains* (i.e. add
them to the resolution list), we use --extra_toolchains.
Once Bazel finds a match, it stops looking.
Using --toolchain_resolution_debug=".*" makes Bazel log
how it is resolving these toolchains and what execution
platform it picked.
* We can also register execution platforms and toolchains in
WORKSPACE.bazel [4], but the flags come with higher priority
and that made resolution a bit tricky. Also, when we want
to conditionally add them (e.g. --config=linux_rbe), we
cannot remove them conditionally in the WORKSPACE.bazel file.
The above resolution flow directly necessitated the changes
in this CL.
Example usage of the new configs and platforms:
# Can be run on a x64 Linux host and uses the hermetic toolchain.
bazel build //:skia_public
# Can be run on Mac or Linux and uses the Linux RBE system along
# with the hermetic toolchain to compile a binary for Linux x64.
bazel build //:skia_public --config=linux_rbe --config=for_linux_x64
# Shorthand for above
bazel build //:skia_public --config=for_linux_x64_with_rbe
Notice we don't have to type out --config=clang_linux anymore!
That was due to me reading the Bazel docs more carefully and
realizing we can set options for *all* Bazel build commands.
Current Limitations:
- Targets which require a py_binary (e.g. Dawn's genrules)
will not work on RBE when cross compiling because the
python runtime we download is for the host machine, not
the executor. This means //example:hello_world_dawn does
not work on Mac when cross-compiling via linux_rbe.
- Mac M1 linking not quite working with SkOpts settings.
Probably need to set -target [5]
Suggested Review order:
- toolchain/BUILD.bazel Notice how we do away with
cc_toolchain_suite for toolchain. These have the same
role: giving Bazel the information about where a toolchain
can run. The platforms one is more expressive (IMO), allowing
us to say both where to run the toolchain and what it can
make. In order to more easily force the use of our hermetic
toolchain, but also allow the hermetic toolchain to be used
on RBE, we specify "use_hermetic_toolchain" only on the target,
because the RBE image does not have the hermetic toolchain
on it by default (but can certainly run it).
- bazel/platform/BUILD.bazel to see the custom constraint_setting
and corresponding constraint_value. The names for both of these
are completely arbitrary - they do not need to have any deeper
meaning or relation to any file or Docker image or system or
any other constraints. Think of the constraint_setting as
an Enum and the constraint_value being the one and only member.
We need to pass around a constant value, not a type, so we
need to provide the constraint_value (e.g. in toolchain/BUILD.bazel)
but not a constraint_setting. However we need a
constraint_setting declared so we can make a constraint_value
of that "type".
Notice the platform declared here - it allows us to force
Bazel to use the hermetic toolchain because of the extra
constraint_value.
- .bazelrc I set a few flags that will be on for all
bazel build commands. Importantly, this causes the C++
build logic to use platforms and not the old, bespoke way.
I also found a way to avoid using the local toolchain on
the host, which will hopefully lead to clearer errors
if platforms are mis-specified instead of odd compile
errors because the host toolchain is too old or something.
There are also a few RBE settings tweaked to be a bit
more modern, as well the new shorthands for specifying
target platforms (e.g. for_linux_x64).
- bazel/buildrc where we have to turn off the platforms
logic for emscripten https://github.com/emscripten-core/emsdk/issues/984
- bazel/rbe/BUILD.bazel for a fix in the platform description
that makes it work on Mac.
- Notice that _m1 has been removed from the mac-related toolchain
files because the same toolchain should work on both
architectures.
- All other changes in any order.
[1] https://bazel.build/docs/toolchains#debugging-toolchains
[2] https://bazel.build/docs/toolchains#toolchain-resolution
[3] https://bazel.build/reference/command-line-reference
[4] https://bazel.build/docs/toolchains#registering-building-toolchains
[5] 17dc3f16fc/gn/skia/BUILD.gn (L258-L271)
Change-Id: I515c114099d659639a808f74e47d489a68b7af62
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/549737
Reviewed-by: Erik Rose <erikrose@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
This reverts commit d78d52a86f.
That reason this CL was reverted in the first place is that it broke the Android roller - perfetto.h could not be located.
We now disable the use of perfetto for Android in the gn_to_bp.py script, so the roller should be good to go.
Reason for revert: Relanding
Original change's description:
> Revert "Add Perfetto library (gn & bazel) and bare-bones SkPerfTrace class"
>
> This reverts commit bfc9b94840.
>
> Reason for revert: new dependency causing Android build error
>
> Original change's description:
> > Add Perfetto library (gn & bazel) and bare-bones SkPerfTrace class
> >
> > First incremental step to incorporating Perfetto tracing into Skia, more CLs to follow
> >
> > NOTE: The presubmit check is failing. This appears to be due to the known issue where the presubmit check bugs out if the DEPS file is edited, which it was on this CL (modified to include Perfetto).
> >
> > Bug: skia:13303
> > Change-Id: I908be0392b520e8da14b34588b842bf6d955bd93
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/543081
> > Reviewed-by: Greg Daniel <egdaniel@google.com>
> > Commit-Queue: Nicolette Prevost <nicolettep@google.com>
>
> Bug: skia:13303
> Change-Id: Ia2b883bbab1f8fb4f3914b63104a39240cc60e86
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/544239
> Reviewed-by: Tyler Denniston <tdenniston@google.com>
> Auto-Submit: Tyler Denniston <tdenniston@google.com>
> Reviewed-by: Nicolette Prevost <nicolettep@google.com>
> Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
> Commit-Queue: Tyler Denniston <tdenniston@google.com>
Bug: skia:13303
Change-Id: Ibd369b9c8c0e69fc9615fc05cf588ee4440c8ed5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/544244
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Nicolette Prevost <nicolettep@google.com>
There are no functional changes to the rules, just a relocation.
Change-Id: I90af5ec792fc54ce2978b0bbb1afd2c932e183b4
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/545719
Reviewed-by: Ben Wagner <bungeman@google.com>
I had to copy some config_settings out of //bazel/common_config_settings
because these are now treated as separate entities and cannot
see that file.
For libpng, note that we use a genrule to create the
pnglibconf.h instead of pointing to one somewhere else.
This ended up being easier than other things I tried.
Another approach would be to not depend on the version
in third_party/externals, but to clone it via
new_git_repository [1] and apply a patch that creates
the configuration file.
[1] https://bazel.build/rules/lib/repo/git#new_git_repository
Bug: skia:12541
Change-Id: I9a284775dc0f2bdabb145518d5f0803c74fb99fa
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/545368
Reviewed-by: Ben Wagner <bungeman@google.com>
This reverts commit bfc9b94840.
Reason for revert: new dependency causing Android build error
Original change's description:
> Add Perfetto library (gn & bazel) and bare-bones SkPerfTrace class
>
> First incremental step to incorporating Perfetto tracing into Skia, more CLs to follow
>
> NOTE: The presubmit check is failing. This appears to be due to the known issue where the presubmit check bugs out if the DEPS file is edited, which it was on this CL (modified to include Perfetto).
>
> Bug: skia:13303
> Change-Id: I908be0392b520e8da14b34588b842bf6d955bd93
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/543081
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Nicolette Prevost <nicolettep@google.com>
Bug: skia:13303
Change-Id: Ia2b883bbab1f8fb4f3914b63104a39240cc60e86
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/544239
Reviewed-by: Tyler Denniston <tdenniston@google.com>
Auto-Submit: Tyler Denniston <tdenniston@google.com>
Reviewed-by: Nicolette Prevost <nicolettep@google.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Tyler Denniston <tdenniston@google.com>
First incremental step to incorporating Perfetto tracing into Skia, more CLs to follow
NOTE: The presubmit check is failing. This appears to be due to the known issue where the presubmit check bugs out if the DEPS file is edited, which it was on this CL (modified to include Perfetto).
Bug: skia:13303
Change-Id: I908be0392b520e8da14b34588b842bf6d955bd93
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/543081
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Nicolette Prevost <nicolettep@google.com>
Rather than having a monolithic third_party/BUILD.bazel, this moves
our Dawn rules to their own subdirectory and makes it callable via
@dawn instead of //third_party/dawn.
This will help with the G3 roll and make our rules more organized in
general.
This also rolls Dawn
Roll Dawn from ab9757036bd6 to e831fb61046b (22 revisions)
https://dawn.googlesource.com/dawn.git/+log/ab9757036bd6..e831fb61046b
Suggested Review Order:
- WORKSPACE.bazel, where we define @dawn and its deps
(@vulkan_headers and @vulkan_tools). I initially thought
I needed to define all of Dawn's deps in the workspace_file_content
for new_local_repository, but that WORKSPACE file is
ignored when building Skia rules.
- third_party/dawn/BUILD.bazel, the contents of which were copied
from //third_party/BUILD.bazel and modified largely via
find-and-replace to point to files relative to
//third_party/externals/dawn. One exception is the cpu_wasm
config_setting because @dawn isn't able to see Skia's
//bazel/macros.bzl.
- All other files
Change-Id: Ib2d7bc972ef00b6b68370ce5c2839ffb70ed9a2f
Bug: skia:12541, skia:13211
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/538638
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
Rolled emsdk to the latest version to get the updated WebGPU wasm
bindings to fix deprecated WebGPU API usage in the ganesh Dawn backend.
The latest WebGPU headers also define the WGPU_WHOLE_MAP_SIZE constant
which is necessary to land a workaround for skia:13266.
* Roll emsdk to 3.1.9
* Fix Dawn backend to use the updated WebGPU API
* Fix -Wunused-but-set-variable warnings
Bug: skia:13220, skia:13266
Change-Id: I57ad39657c3013f384620302ab12a71ffc426c12
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/534945
Commit-Queue: Arman Uguray <armansito@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
To make it easier to use the G3 version of this dep,
we make a reference to it in the WORKSPACE.bazel, so
we can refer to this external dep with the @ notation.
I would like to do this for all of our third party
deps, but one at a time.
Change-Id: I03e0beca124225e0faf1232278dae641da8a3e4d
Bug: skia:13240, skia:13211
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/535358
Reviewed-by: Joe Gregorio <jcgregorio@google.com>
A new RBE worker-pool called gce_linux was created in
conjunction with this CL. See
https://docs.google.com/document/d/14xMZCKews69SSTfULhE8HDUzT5XvPwZ4CvRufEvcZ74/edit#
for some details on that.
Note: everything under bazel/rbe/gce_linux was autogenerated
and can be ignored from manual review. It basically specifies
what files are on the RBE image that are necessary for running
Bazel.
Testing it out can be done by authenticating for RBE
gcloud auth application-default login --no-browser
Then, run make -C bazel rbe_known_good_builds
to test it out.
On my 4 core laptop with an empty local cache, but a
warm remote cache, the build took <2 min instead of the
10+ minutes it would have [1].
The folder structure in //bazel/rbe is meant to let us
have multiple remote configurations there, e.g.
//bazel/rbe/gce_windows.
Suggested Review Order:
- bazel/rbe/README.md
- bazel/rbe/gce_linux_container/Dockerfile to see the
bare-bones RBE image.
- bazel/rbe/BUILD.bazel to see a custom platform defined.
It is nearly identical to the autogenerated one
in bazel/rbe/gce_linux/config/BUILD, with one extra
field to force the gce_linux pool to be used.
- .bazelrc to see the settings needed to make
--config=linux-rbe work. The naming convention was
inspired by SkCMS's setup [2], and allows us to have
some common RBE settings (i.e. config:remote) and
some specialized ones for the given host machine
(e.g. config:linux-rbe) A very important, but subtle
configuration, is on line 86 of .bazelrc where we say
to use our hermetic toolchain and not whatever C++
compiler and headers are on the host machine (aka
the RBE container).
- toolchain/build_toolchain.bzl to see some additional
dependencies needed in the toolchain (to run IWYU) which
I had installed locally but didn't realize were important.
- third_party/BUILD.bazel to see an example of how failing
to specify all files can result in something that works
locally, but fails remotely.
--execution_log_json_file=/tmp/execlog.json helped debug
these issues.
- All other files.
[1] http://go/scrcast/NjM1ODE4MDI0NzM3MTc3Nnw3ODViZmFkMi1iOA
[2] https://skia.googlesource.com/skcms/+/30c8e303800c256febb03a09fdcda7f75d119b1b/.bazelrc#20
Change-Id: Ia0a9e6a06c1a13071949ab402dc5d897df6b12e1
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/524359
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
The file generation logic that dawn [1] uses to make some
source files requires jinja2, which also requires MarkupSafe.
The GN build handles this by specifying those repos in
DEPS, checking them out at a certain git hash, and then
providing them via a command line arg [2].
We do not have to do it this way in Bazel to have reproducible
builds. This CL specifies an exact version (verified by sha256)
of those two deps and then uses a hermetic version of
Python 3.9 to run all py_binary commands.
Previously, we would rely on the system Python (and installed
libraries). That happened to work on my machine, but not on
other machines without jinja2 and MarkupSafe installed. After
this CL, it should work on machines that do not have python
even installed.
I chose the same jinja2 version used by Dawn [3], which was
2.11.3. Then I chose the newest version of MarkupSafe that
was compatible with jinja2 (2.0.1).
If we have other python scripts that need external deps, we
should be able to specify them in the py_binary that needs
them and in requirements.txt. Then, the pip_install() step
in WORKSPACE.bazel will download them and make them available.
[1] https://dawn.googlesource.com/dawn.git/+/refs/heads/main/docs/dawn/overview.md
[2] https://dawn.googlesource.com/dawn.git/+/e45ff6a4b3c2f06dade68ec0f01ddc3bfd70c282/generator/generator_lib.gni#77
[3] ee69aa00ee
Change-Id: I3d0074f3003de179400e239e00107c34f35f4901
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/524217
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
sk_app has existing support for Dawn on top of Vulkan, and
this adds support to build //example:hello_world_dawn and
get this to run on Linux.
Dawn depends on Tint and abseil-cpp. Tint further depends on
spirv_tools and spirv_headers (for writing to the SPIR-V format).
Dawn and Tint only have GN and CMake support, so we need to make
our Bazel rules for them (see //third_party/BUILD.bazel).
abseil-cpp and the SPIR-V libraries have Bazel support, so we
can just include them (see //WORKSPACE.bazel). It is important
that @spirv_headers be called that exactly because @spirv_tools
depends on it by that name.
The hand-crafted cc_library rules for Dawn and Tint were produced
by reading the appropriate GN files and using the parts necessary
for a supporting Vulkan+Linux. If we use Dawn for other backends
(e.g. WebGPU), we will need to expand the Bazel rules. One day,
we might contribute the Bazel rules to Dawn and Tint so they
can support them and avoid breaking us if new files are added.
Suggested Review Order
- bazel/common_config_settings/BUILD.bazel to see introduction
of new select-able option "has_gpu_backend" which cleans up
some of our code that is enabled for any GPU backend.
- src/*/BUILD.bazel to see has_gpu_backend rolled out.
- WORKSPACE.bazel to see DEPS declared there (using the files
in third_party/externals, which are brought in via
tools/git-sync-deps).
- third_party/BUILD.bazel which adds Dawn and Tint rules.
It may be helpful to look in third_party/externals for
the Dawn [1] and Tint [2] GN files. Especially interesting
are the Python scripts [3] Dawn uses to generate some
header and source files.
- All other files.
[1] https://dawn.googlesource.com/dawn/+/d9f22ce0346b222759d5510be3d1cd93caa5ab86/src/dawn/native/BUILD.gn#183
[2] https://dawn.googlesource.com/tint/+/453d5ae84ec30ab51ac592c13d472412ae8b5fc9/src/tint/BUILD.gn#174
[3] https://dawn.googlesource.com/dawn/+/d9f22ce0346b222759d5510be3d1cd93caa5ab86/generator/dawn_json_generator.py#774
Change-Id: Ied5b162045d8e841b9666457f0158457e2b078d4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/516996
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
One very important, but agonizing to discover, change was
to go_repositories.bzl. Without it, we see cryptic errors like:
external/org_chromium_go_luci/cipd/api/cipd/v1/BUILD.bazel:22:17: no such package '@org_chromium_go_luci//go.chromium.org/luci/cipd/api/cipd/v1': BUILD file not found in directory 'go.chromium.org/luci/cipd/api/cipd/v1' of external repository @org_chromium_go_luci. Add a BUILD file to a directory to mark it as a package. and referenced by '@org_chromium_go_luci//cipd/api/cipd/v1:api_go_proto'
The rest of these changes are very similar to
https://skia-review.googlesource.com/c/buildbot/+/514074
which also has justification for the use of task drivers,
even in a Bazel-driven world.
All the BUILD.bazel files under infra/bots/task_drivers were
generated by Gazelle.
Note that the infra/bots/BUILD.bazel can happily build and
package up the task drivers from the infra repo. The old
build_task_drivers tasks did this too, because we have some
task drivers that are used in both repos.
Change-Id: I13c46c62bc7a6a4bfe7935b28efbfb34caabb6f2
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/515296
Reviewed-by: Eric Boren <borenet@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
Run the tests in headless mode and output the logs
bazel test :hello_world --test_output=all
Start up a visible web browser with the karma test driver
(need to go to Debug tab to actually run tests)
bazel run :hello_world
Suggested review order
- package.json to see the karma dependencies to run
jasmine tests on chrome and firefox.
- WORKSPACE.bazel to see how the packages listed in
package.json and package-lock.json are downloaded
into the Bazel sandbox/cache via the npm_install rule.
As mentioned in the package.json comment, the version
of build_bazel_rules_nodejs which emscripten uses [1]
is 4.4.1 and if we tried to install it ourselves, that
installation will be ignored. We also bring in hermetic
browsers via io_bazel_rules_webtesting.
- bazel/karma_test.bzl which defines a new rule _karma_test
and a macro karma_test which joins the new rule with
an existing web_test rule to run it on a hermetic browser
which Bazel downloads. This rule takes heavy inspiration
from @bazel/concatjs [2], but is much simpler and lets us
configure more things (e.g. proxies, so we can work with
test_on_env).
- karma.bazel.js, which is a pretty ordinary looking karma
configuration file [2] with effectively a JS macro
BAZEL_APPLY_SETTINGS. JS doesn't have a preprocessor or
actual macros, but this string will be replaced by the
JS code in karma_test.bzl which will set correct filepaths
for Bazel content.
- All other files.
[1] c33c7be17f/bazel/deps.bzl (L10)
[2] 700b7a3c5f/packages/concatjs/web_test/karma_web_test.bzl (L318)
[3] http://karma-runner.github.io/6.3/config/configuration-file.html
Change-Id: Id64c0a86d6be37d627762cef0beaaf23ad390ac1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/509717
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
PS1 regenerates the BUILD.bazel files
This allows us to use closure to minify the JS in canvaskit.js
Change-Id: Ib8326d2e3a19cd2168b740b6946f9165a2810133
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/509177
Reviewed-by: Ben Wagner <bungeman@google.com>
- We always download from https
- All external assets have a primary and a mirror URL.
- We prioritize the sources as follows:
bazel mirror, github/original source, our mirror
- There is a way (see build_toolchain) to test the sources
from the mirrors (done before CL submission).
This adds a utility to upload files to the mirror in a
consistent, scripted way. It includes a way to copy in
parts of our bazel files (e.g. debs_to_install from
toolchain/build_toolchain.bzl) to update many things
at once.
Our Bazel mirror (gs://skia-world-readable/bazel)
is a Content Addressable Storage system, where the
file name is based on the sha256sum of the contents
(the same hash that Bazel uses). All files in it should
be publicly accessible.
Change-Id: Ida8b8e07d27a0a557bc49467ebbc86c806cabbd3
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/494478
Reviewed-by: Joe Gregorio <jcgregorio@google.com>
bazel run //example:hello_world --config=clang
causes a window to open and draws a circle and a square.
Text to follow in a future CL.
To make this work, I had to get rid of musl and use glibc.
All the shared libraries (.so files) that were pre-built
and available for download (e.g. from https://packages.debian.org/bullseye/amd64/libgl1/download)
were compiled against glibc. When I tried to run a
program statically linked with musl and dynamically linked
against things using glibc, I got a segmentation fault
on things like calloc().
Initial attempts to use glibc had failed because it was thought
that the libc.so.6 file could only be referred to by absolute
path (and thus Bazel would not be happy about it). As it turns out,
that was simply a misconfiguration of the builtin_sysroot
parameter to cc_common.create_cc_toolchain_config_info
(see //toolchain/clang_toolchain_config.bzl). By setting that
to `external/clang_linux_amd64` and not
`external/clang_linux_amd64/usr`, the libc binary which had
been extracted to `external/clang_linux_amd64/lib/x86_64-linux-gnu`
was perfectly reachable from
`external/clang_linux_amd64/usr/usr/lib/x86_64-linux-gnu/libc.so`
To bring in the shared libraries to link against (e.g. X11, GL)
I made build_toolchain.bzl easier to modify in that we simply need
to add a debian download url and sha256 hash to a list (rather than
having to plumb this through via arguments).
Recommended Review Order:
- example/BUILD.bazel (not sure if we always want to set bare
link arguments like that or if we want to use "features" to
pass those along to the toolchain).
- tools/sk_app/BUILD.bazel to see initial cc_library for
wrapping sk_app code.
- toolchain/build_toolchain.bzl to see removal of musl and
new list of debs.
- toolchain/clang_toolchain_config.bzl (where use of the
no-canonical-prefixes was key to compilation success).
Notice also that we statically linked libc++ (I did not
have any shared libraries for it locally, so I guessed
a typical developer might not either).
- Rest of toolchain/ for trivial renames.
- bazel/Makefile to see extra docs on those targets and
a new target that compiles all the exes so far for a
quick way to test the build.
- third_party/BUILD.bazel and src/gpu/BUILD.bazel which have
non-generated changes. (all other BUILD.bazel files do).
- go.mod, which needed to update the infra repo version in
order to pick up http://review.skia.org/491736).
Change-Id: I8687bd227353040eca2dffa9465798d8bd395027
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/492117
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
- Use latest emscripten toolchain (3.1.0)
- Autogenerate the atoms and manually fix some of the file lists.
- Add a known_good_builds target to bazel/Makefile to help
check the things we expect to work with Bazel.
Change-Id: Ia5f51e7b9eb5c108386820ad59180c8f862f5a70
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/491438
Reviewed-by: Ben Wagner <bungeman@google.com>
This adds a simple go program to test the installed go
toolchain, and a Make rule to codify the arguments to
our gazelle binary, built with extensions.
I could not figure out how to get the .json file to work
with the gazelle() Bazel rule, but this works ok for now.
Bug: skia:12541
Change-Id: I5067b15c7518951aeb69559d3871799d3b5745f4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/475716
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
This re-works src/ports/BUILD.bazel to work like our other
BUILD files, i.e. one rule "srcs" that brings in the necessary
private filegroups.
To work around an abort with LLVM [1], we have to go back to an
earlier version of emscripten (temporarily?).
Future work should look at using transitions [2] to allow various
executables (e.g. CanvasKit, DM) to set their own set of Bazel
flags, w/o the build invokers having to specify them.
These transitions might be able to handle more complex cases
that we currently use if statements in GN to deal with.
The Freetype build rule was created by taking the BUILD.gn
rule, adding in all the sources listed there and then playing
compile-whack-a-mole to add in all the headers and included
.c files.
Suggested Review Order:
- third_party/BUILD.bazel to see freetype build rules
- bazel/common_config_settings/ to see treatment of fontmgr
like codecs (many possible) and fontmgr_factory (only one).
- src/ports/BUILD.bazel
- BUILD.bazel
- modules/canvaskit/BUILD.bazel. Take note of the gen_rule that
calls tools/embed_resources.py to produce the .cpp file
containing the embedded font data.
- Everything else.
[1] https://github.com/emscripten-core/emscripten/issues/15528
[2] https://github.com/bazelbuild/examples/tree/main/rules/starlark_configurations/cc_binary_selectable_copts
Bug: skia:12541
Change-Id: I08dab82a901d80507007b354ca20cbfad2c2388f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/471636
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
These rules can be used to build our GMs on WASM+WebGL and
libskia.a with just the CPU backend (and most other features
turned off).
This can be done with the following commands:
- bazel build //modules/canvaskit:gm-bindings-wasm --gpu_backend=gl_backend --with_gl_standard=webgl_standard
- bazel build :skia-core --config clang
This pivots slightly from http://review.skia.org/463517
by using config_settings [1] instead of platforms for
the optional features that we control. This pivot was
suggested in [2]
We have BUILD.bazel files in many of the subdirectories
that specify filegroups for the appropriate files. In
an effort to make //BUILD.bazel more readable, it is
the responsibility of these subfolders to deal with
conditionally including certain .h or .cpp files.
This is done using select statements and config_settings
or platform constraints as necessary.
For example, src/gpu/BUILD.bazel will different private
filegroups for each of the supported gpu backends [3]
and a more-visible filegroup called "srcs" that has
the right selection of the private files to be used
for compilation.
An effort has been made to avoid using glob() in our
BUILD.bazel files. These file lists were made by using
`ls -1` and some regex to add in quotes. We might want
to make a helper script to assist with that, if necessary.
To specify which options we have, the settings in
//bazel/common_config_settings/BUILD.bazel have been
redesigned. They make use of a macro `string_flag_with_values`
that removes the boilerplate. Patchset 36 shows what the
file looks like w/o the macro.
The top level BUILD.bazel file will still need to use
some logic to handle defines, because local_defines is
a list of strings, not a list of labels [4].
Suggested Review Order:
- WORKSPACE.bazel to see the new dependencies on the
emsdk toolchain and bazel_skylib
- bazel/common_config_settings/* to see the few settings
defined (we have more to define, see BUILD.gn and
//gn/skia.gni for ideas)
- BUILD.bazel to see the "skia-core" cc_library rule.
See also "gms" and "tests"
- modules/canvaskit/BUILD.bazel to see the use of
the emscripten "wasm_cc_binary" rule, which depends
on the "skia-core", "gms", and "tests" rule. Note that
it only builds some of the gms as a proof of concept.
- The other BUILD.bazel files. Some of these are not
platform or feature dependent (e.g. pathops). Others
are (e.g. gpu).
- All other files.
[1] https://docs.bazel.build/versions/4.2.1/skylark/config.html#user-defined-build-settings
[2] https://github.com/emscripten-core/emsdk/pull/920
[3] In this CL, that's just the webgl one.
[4] https://docs.bazel.build/versions/main/be/c-cpp.html#cc_library.local_defines
Change-Id: Ieecf9c106d5e3a6ae97d13d66be06b4b3c207089
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/458637
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Owners-Override: Kevin Lubick <kjlubick@google.com>
This can successfully build a C library:
bazel build --config=clang //third_party:libpng
This can build and run a statically-linked executable:
bazel test --config=clang //:bazel_test
For more verbose compile and linking output, add the
`--features diagnostic`
flag to a Bazel command (see _make_diagnostic_flags() in
toolchain/clang_toolchain_config.bzl. Similarly, a
`--features print_search_dirs` can be used to show where
clang is looking for libraries etc to link against.
These features are made available for easier debugging.
Suggested review order:
- Read https://docs.bazel.build/versions/4.2.1/tutorial/cc-toolchain-config.html
if unfamiliar with setting up C++ toolchains in Bazel
- .bazelrc and WORKSPACE.bazel that configure use and download
of the toolchain (Clang 13, musl 1.2.2)
- toolchain/build_toolchain.bzl which downloads and assembles
the toolchain (w/o installing anything on the host machine)
- toolchain/BUILD.bazel and toolchain/*trampoline.sh to see
the setup of the toolchain rules.
- toolchain/clang_toolchain_config.bzl to see the configuration
of the toolchain. Pay special attention to the various
command line flags that are set.
- See that tools/bazel_test.cc has made a new home in
experimental/bazel_test/bazel_test.cpp, with a companion
BUILD.bazel. Note the addition of some function calls
that test use of the C++ standard library.
The number being used to test the PNG library is the latest
and greatest that verifies we are compiling the one brought
in via DEPS (and not a local one).
- third_party/* to see how png (and its dependent zlib) have
been built. Pay special attention to the musl_compat hack
to fix static linking (any idea what the real cause is?)
- //BUILD.bazel to see definition of the bazel_test executable.
Change-Id: I7b0922d0d45cb9be8df2fd5fa5a1f48492654d5f
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/461178
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
A few first steps toward a Bazel build.
To try it out, I think just
$ bazel test ...
I added third_party to .bazelignore to prevent Bazel from looking there.
It can handle external dependencies itself, so no need to poke into what
we sync from DEPS. Some of those have Bazel configs and we don't want
to be building them yet.
I've started by with libpng using new_git_repository(), mostly because
it's small, with a mildly complex build, and needs dependencies of its
own, zlib. Mysteriously zlib is built-in to Bazel, so that was easy.
Next up is probably a dependency that does support Bazel, using
git_repository(). That should make sure we can handle the full mix.
Change-Id: I5775a1b254d341b9a90630aa1cc433a24167f2fd
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/316636
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Joe Gregorio <jcgregorio@google.com>
