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>
As a follow-up to https://skia-review.googlesource.com/c/skia/+/476219,
this sketches out how we can maybe use cc_library for the things
in //modules to make sure something in //src doesn't depend on
anything in //modules, for example.
The following succeeds:
bazel build //modules/skparagraph:skparagraph --config=clang \
--shaper_backend=harfbuzz_shaper --with_icu
As does `make bazel_canvaskit_debug` in //modules/canvaskit
Suggested Review Order:
- third_party/BUILD.bazel for ICU and harfbuzz rules. Pay
special attention to the genrules used to call the python
script for turning the icu .dat file into .S or .cpp.
- bazelrc and bazel/ for new flags and defines that control
use of ICU and harfbuzz. Unlike GN, with the public_defines
that get added in automatically if icu or harfbuzz is
depended upon, we need to set the defines at the top level.
This necessity might go away if we change the atoms to
depend on //modules/skshaper, which could define that flag.
- Top level BUILD.bazel files in //modules/skparagraph,
//modules/skshaper, //modules/skunicode, //modules/canvaskit
- All other .bazel file changes are automatic.
Bug: skia:12541
Change-Id: I38a9e0a9261d7e142eeb271c2ddb23f362f91473
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/478116
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
To make the atomic rules a bit easier to work with, in many
of the folders, this adds in cc_library rules to group
together the sources from that folder (and subfolders
where prudent). We only needs sources because those atoms
should have their headers as deps.
One issue that was pointed out is that there is currently
no way to restrict the inclusion of certain packages,
a la, `gn check`. For example, there is no mechanism from
stopping a dev from adding
#include "modules/canvaskit/WasmCommon.h"
to something in //src/core (except circular dependencies).
We can probably address that using Bazel's visibility
rules as needed:
https://docs.bazel.build/versions/main/visibility.htmlhttps://docs.bazel.build/versions/main/be/functions.html#package_group
It is recommended to look at this CL patchset by patchset.
PS1: Update gazelle command to generate rules in more folders.
PS2: A few changes to make generation work better.
PS3: The result of running make generate in //bazel
PS4: Adding the rules to build sksllex, the simplest binary I
could find in the Skia repo.
PS5: Adding the rules to build skdiff, a more complex binary.
I tried a few approaches, but ended up gravitating back
towards the layout where we have each folder/package
group up the sources. I imagine at some point, we'll have
skdiff depend on skia_core or something, which will
have things like //src/core, //src/codecs, //src/pathops
all bundled together.
PS7: Added in the groupings of sources, similar to what we had
earlier. I liked these for readability. These helped fix
up the //:skia_core build, and by extension, the CanvasKit
build.
Change-Id: I3faa7c4e821c876b243617aacf0246efa524cbde
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/476219
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@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 uses the gazelle extension from
https://skia-review.googlesource.com/c/buildbot/+/473357
Review Tips:
- Ignore any changes to .h or .cpp files. Those have been
pulled out into their own CLs.
- Start with bazel/macros.bzl.
- Read the CL with the generation code, if you haven't already.
- Look at third_party/file_map_for_bazel.json.
- See experimental/bazel_test for an idea of how a cc_binary
would be made.
- Spot check one or two of the BUILD.bazel files.
This CL generates the "atomic" rules for src/, include/ and
modules/skshaper, as a starting point.
`bazel build --config clang //include/...` works
`bazel build --config clang //src/...` starts compiling,
(which verifies that the BUILD.bazel files are all valid),
but runs into errors because not all third_party deps have
been resolved, and there are some files missing from the
toolchain still (e.g. EGL headers).
Change-Id: Ib7e0fb0efdb9f08655f06cbc56e9bb4cf416294b
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/474240
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
This will hopefully let us pre-package certain binaries (e.g. DM,
fuzz) with more sensible defaults and not make the developer
type out all the settings.
For CanvasKit, which specifies its own build flags, I think I'll
need to make another transition setup, which would go in something
like modules/canvaskit/ck_binary_with_flags.bzl or something.
Some sausage-case-names were converted to snake_case_names as per
go/build-style#target-naming
The example this is based off is worth a look through before
diving into this:
https://github.com/bazelbuild/examples/tree/main/rules/starlark_configurations/cc_binary_selectable_copts
Change-Id: Ia919d47f4d1aa25cf294af7918e36d38838c179e
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/472688
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Importantly, this adds options for encoding using
certain codecs, not just decoding.
Change-Id: I4a610ebf985b67d4545c71b3f3eed4c7807e6a26
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/472277
Reviewed-by: Ben Wagner <bungeman@google.com>
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>
This ports the third_party BUILD.gn files related to codecs
(with a best-effort on arm/SIMD stuff). This includes:
- libpng
- libjpeg-turbo
- libwebp
- wuffs (gif)
- libgifcodec
- dng_sdk and piex (raw codec)
This expands the string_flag_with_values macro to allow
multiple values to be set at once. This was added in Bazel 5.0.0,
however the latest pre-release version of that has a bug [1]
which slows down compilation dramatically. This was fixed at
ToT, but not released. As a result, I started using the Bazel
6 pre-release (via bazelisk).
The macro select_multi makes writing select() where multiple
elements could be on possible/easier.
One can try compiling certain codecs by running:
bazel build :skia-core --config clang --include_codec=raw_codec --include_codec=png_codec
Suggested Review Order:
- bazel/macros.bzl
- bazel/common_config_settings/defs.bzl and its BUILD.bazel
to see how the codec options are defined.
- BUILD.bazel to see how the codec settings are used.
- src/codec/BUILD.bazel to see the inclusion of Skia files to
deal with specific codecs.
- third_party/BUILD.bazel (while referencing the corresponding
BUILD.gn files, such as third_party/libwebp/BUILD.gn)
- Everything else.
Change-Id: I797375a35fa345d9835e7b2a2ab23371c45953c3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/469456
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leon Scroggins <scroggo@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 makes use of Bazel's pre-defined platforms
https://github.com/bazelbuild/platforms
and some of our own defined values (see
//bazel/common_config_settings/BUILD.bazel) to customize
the build rules.
I verified this by building bazel_test locally for
linux x64 as well as using the third_party deps for
a WASM build (using build files not seen in this CL).
Suggested Review Order:
- https://docs.bazel.build/versions/main/platforms.html if not
already familiar with Bazel Platforms
- third_party/BUILD.bazel to see that 1) all globs have
been removed and 2) select() targets various
platform constants or groups of constants to control
sources, headers, and local_defines.
- common_config_settings/ to see the groups of constraints
created, as well as new constraint_settings defined
(skdebug_impl)
- supported_combinations/ to see how we can define supported
sets of the constraint values (aka Bazel platforms).
I imagine expanding this more, so we might have platforms
named "linux_x64_emptyfontmgr_vulkan" or such.
- //BUILD.bazel and bazel_test.cpp to see use of SkDebugf.
- Everything else.
Change-Id: I49e4abdbcf7b76f0674efdbb1f53dc8823d110ee
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/463517
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Owners-Override: Kevin Lubick <kjlubick@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>
