unregister default toolchains; update README
This commit is contained in:
Motiejus Jakštys
parent
62849afc7a
commit
3e7f92cea5
@ -9,6 +9,9 @@ environment:
|
||||
tasks:
|
||||
- setup: |
|
||||
sudo apt-get purge gcc -y && sudo apt-get autoremove -y
|
||||
- test_list_toolchains: |
|
||||
cd bazel-zig-cc; . .envrc; echo "Available toolchains:"
|
||||
bazel query @zig_sdk//... | sed -En '/.*_toolchain$/ s/.*:(.*)_toolchain$/\1/p'
|
||||
- test_default: |
|
||||
cd bazel-zig-cc; . .envrc; ./build-and-file \
|
||||
//test:hello | \
|
||||
|
||||
89
README.md
89
README.md
@ -2,17 +2,12 @@
|
||||
|
||||
# Bazel zig cc toolchain
|
||||
|
||||
This is an early stage zig-cc toolchain that can cross-compile C/C++ programs
|
||||
(including cgo) to these os/archs:
|
||||
|
||||
- amd64-linux-gnu.2.19
|
||||
- amd64-linux-musl
|
||||
- arm64-linux-gnu.2.28
|
||||
- arm64-linux-musl
|
||||
- amd64-macos
|
||||
- arm64-macos
|
||||
|
||||
... and more.
|
||||
This is a C/C++ toolchain that can (cross-)compile C/C++ programs. It contains
|
||||
clang-12, musl, glibc (versions 2-2.33, selectable), all in a ~40MB package.
|
||||
Read
|
||||
[here](https://andrewkelley.me/post/zig-cc-powerful-drop-in-replacement-gcc-clang.html)
|
||||
about zig-cc; the rest of the README will present how to use this toolchain
|
||||
from Bazel.
|
||||
|
||||
# Usage
|
||||
|
||||
@ -30,11 +25,34 @@ http_archive(
|
||||
|
||||
load("@bazel-zig-cc//toolchain:defs.bzl", zig_register_toolchains = "register_toolchains")
|
||||
|
||||
zig_register_toolchains()
|
||||
zig_register_toolchains(["x86_64-linux-gnu.2.28", "x86_64-macos-gnu"])
|
||||
```
|
||||
|
||||
This will register the "default" toolchains. Look into `register_toolchains` on
|
||||
which parameters it accepts.
|
||||
The snippet above will download the zig toolchain and register it for the
|
||||
following platforms:
|
||||
|
||||
- `x86_64-linux-gnu.2.28` for `["@platforms//os:linux", "@platforms//cpu:x86_64"]`.
|
||||
- `x86_64-macos-gnu` for `["@platforms//os:macos", "@platforms//cpu:x86_64"]`.
|
||||
|
||||
Note that both Go and Bazel naming schemes are accepted. For convenience with
|
||||
Go, the following Go-style toolchain aliases are created:
|
||||
|
||||
|Bazel (zig) name |Go name|
|
||||
--- | ---
|
||||
|`x86_64`|`amd64`|
|
||||
|`aarch64`|`arm64`|
|
||||
|`macos`|`darwin`|
|
||||
|
||||
For example, the toolchain `linux_amd64_gnu is aliased to
|
||||
`x86_64-linux-gnu.2.28`. .2.28`.
|
||||
|
||||
To find out which toolchains can be registered or used, run this:
|
||||
|
||||
```
|
||||
$ bazel query @zig_sdk//... | sed -En '/.*_toolchain$/ s/.*:(.*)_toolchain$/\1/p'
|
||||
```
|
||||
|
||||
This is still work in progress; please read [#Known Issues] before using.
|
||||
|
||||
# Testing
|
||||
|
||||
@ -81,11 +99,46 @@ how CI does it.
|
||||
|
||||
# Known Issues
|
||||
|
||||
- [ziglang/zig #9485 glibc 2.27 or older: fcntl64 not found, but zig's glibc headers refer it](https://github.com/ziglang/zig/issues/9485)
|
||||
- [ziglang/zig #9431 FileNotFound when compiling macos](https://github.com/ziglang/zig/issues/9431)
|
||||
- [rules/go #2894 Per-arch_target linker flags](https://github.com/bazelbuild/rules_go/issues/2894)
|
||||
## Parallel `zig c++` invocations may fail
|
||||
|
||||
Closed issues:
|
||||
Task: [ziglang/zig #9431 FileNotFound when compiling macos](https://github.com/ziglang/zig/issues/9431)
|
||||
|
||||
Background: there is a race when calling `zig c++`, which Bazel does a lot.
|
||||
This may fail compilation. Yours truly only reproduced it on macos with a cold
|
||||
cache. Based on that, a workaround in the toolchain exists, named
|
||||
`speed_first_safety_later`. The possible values are `auto` (default), `yes`,
|
||||
`no`.
|
||||
|
||||
## glibc 2.27 or older
|
||||
|
||||
Task: [ziglang/zig #9485 glibc 2.27 or older: fcntl64 not found, but zig's glibc headers refer it](https://github.com/ziglang/zig/issues/9485)
|
||||
|
||||
Background: when glibc 2.27 or older is selected, it may miss `fcntl64`. A
|
||||
workaround is applied for `x86_64`, but not for aarch64. The same workaround
|
||||
may apply to aarch64, but the author didn't find a need to test or ensure it
|
||||
(yet).
|
||||
|
||||
## cgo for darwin (macos)
|
||||
|
||||
Task: [rules/go #2894 Per-arch_target linker flags](https://github.com/bazelbuild/rules_go/issues/2894)
|
||||
|
||||
Background: this toolchain needs an extra step to be used for Darwin (macos)
|
||||
targets. Specifically, one needs to add `gc_linkopts` for every `go_binary`:
|
||||
|
||||
```
|
||||
go_binary(
|
||||
<...>
|
||||
gc_linkopts = select({
|
||||
"@platforms//os:macos": ["-s", "-w", "-buildmode=pie"],
|
||||
"//conditions:default": [],
|
||||
}),
|
||||
)
|
||||
```
|
||||
|
||||
Until the linked task is resolved, this needs to be done for every `go_binary`
|
||||
that is meant to be compiled to Darwin.
|
||||
|
||||
# Closed issues
|
||||
|
||||
- [ziglang/zig #9139 zig c++ hanging when compiling in parallel](https://github.com/ziglang/zig/issues/9139) (CLOSED)
|
||||
- [golang/go #46644 cmd/link: with CC=zig: SIGSERV when cross-compiling to darwin/amd64](https://github.com/golang/go/issues/46644) (CLOSED)
|
||||
|
||||
@ -53,4 +53,11 @@ load(
|
||||
zig_register_toolchains = "register_toolchains",
|
||||
)
|
||||
|
||||
zig_register_toolchains(speed_first_safety_later="auto")
|
||||
_REGISTER_TOOLCHAINS = [
|
||||
"linux_arm64_gnu.2.28",
|
||||
"linux_amd64_gnu.2.19",
|
||||
"darwin_amd64",
|
||||
"darwin_arm64",
|
||||
]
|
||||
|
||||
zig_register_toolchains(register = _REGISTER_TOOLCHAINS)
|
||||
|
||||
@ -56,13 +56,6 @@ _GLIBCS = [
|
||||
"2.33",
|
||||
]
|
||||
|
||||
DEFAULT_TOOLCHAINS = [
|
||||
"linux_arm64_gnu.2.28", # There is a problem with fcntl on arm64, this is WIP
|
||||
"linux_amd64_gnu.2.19", # Debian Jessie amd64
|
||||
"darwin_amd64",
|
||||
"darwin_arm64",
|
||||
]
|
||||
|
||||
def _target_darwin(gocpu, zigcpu):
|
||||
return struct(
|
||||
gotarget = "darwin_{}".format(gocpu),
|
||||
@ -146,8 +139,16 @@ def _target_linux_musl(gocpu, zigcpu):
|
||||
)
|
||||
|
||||
def register_toolchains(
|
||||
register = DEFAULT_TOOLCHAINS,
|
||||
register = [],
|
||||
speed_first_safety_later = "auto"):
|
||||
"""
|
||||
Download zig toolchain and register some.
|
||||
@param register registers the given toolchains to the system using
|
||||
native.register_toolchains(). See README for possible choices.
|
||||
@param speed_first_safety_later is a workaround for
|
||||
https://github.com/ziglang/zig/issues/9431
|
||||
"""
|
||||
|
||||
zig_repository(
|
||||
name = "zig_sdk",
|
||||
# Pre-release:
|
||||
@ -311,10 +312,6 @@ def zig_build_macro(absolute_path, zig_include_root):
|
||||
for target_config in _target_structs():
|
||||
gotarget = target_config.gotarget
|
||||
zigtarget = target_config.zigtarget
|
||||
native.platform(
|
||||
name = gotarget,
|
||||
constraint_values = target_config.constraint_values,
|
||||
)
|
||||
|
||||
cxx_builtin_include_directories = []
|
||||
for d in DEFAULT_INCLUDE_DIRECTORIES + target_config.includes:
|
||||
@ -341,7 +338,7 @@ def zig_build_macro(absolute_path, zig_include_root):
|
||||
copts = copts + ["-include", absolute_path + "/" + incl]
|
||||
|
||||
zig_cc_toolchain_config(
|
||||
name = zigtarget + "_cc_toolchain_config",
|
||||
name = zigtarget + "_toolchain_cc_config",
|
||||
target = zigtarget,
|
||||
tool_paths = absolute_tool_paths,
|
||||
cxx_builtin_include_directories = cxx_builtin_include_directories,
|
||||
@ -356,9 +353,9 @@ def zig_build_macro(absolute_path, zig_include_root):
|
||||
)
|
||||
|
||||
native.cc_toolchain(
|
||||
name = zigtarget + "_cc_toolchain",
|
||||
name = zigtarget + "_toolchain_cc",
|
||||
toolchain_identifier = zigtarget + "-toolchain",
|
||||
toolchain_config = ":%s_cc_toolchain_config" % zigtarget,
|
||||
toolchain_config = ":%s_toolchain_cc_config" % zigtarget,
|
||||
all_files = ":zig",
|
||||
ar_files = ":zig",
|
||||
compiler_files = ":zig",
|
||||
@ -375,7 +372,7 @@ def zig_build_macro(absolute_path, zig_include_root):
|
||||
name = gotarget + "_toolchain",
|
||||
exec_compatible_with = None,
|
||||
target_compatible_with = target_config.constraint_values,
|
||||
toolchain = ":%s_cc_toolchain" % zigtarget,
|
||||
toolchain = ":%s_toolchain_cc" % zigtarget,
|
||||
toolchain_type = "@bazel_tools//tools/cpp:toolchain_type",
|
||||
)
|
||||
|
||||
@ -384,6 +381,6 @@ def zig_build_macro(absolute_path, zig_include_root):
|
||||
name = zigtarget + "_toolchain",
|
||||
exec_compatible_with = None,
|
||||
target_compatible_with = target_config.constraint_values,
|
||||
toolchain = ":%s_cc_toolchain" % zigtarget,
|
||||
toolchain = ":%s_toolchain_cc" % zigtarget,
|
||||
toolchain_type = "@bazel_tools//tools/cpp:toolchain_type",
|
||||
)
|
||||
|
||||
Loading…
Reference in New Issue
Block a user