Support to fetch remote toolchain package when building project

[waruqi]

we can fetch cross toolchain or the special version of clang/gcc/llvm/mingw

Supported toolchains in xmake-repo

• llvm
• gnu-rm
• muslcc (musl.cc)
• llvm-mingw
• zig

set_toolchains

toolchain_name@package_name_or_alias

add_requires("llvm 11.x", {alias = "llvm-11"})
set_toolchains("llvm@llvm-11")

@toolchain_package_name

if toolchain name and package name are same

add_requires("llvm")
set_toolchains("@llvm")

Only use toolchain, do not bind toolchain package

It will not fetch remote toolchain package.

set_toolchains("llvm")

fetch cross toolchain

add_requires("muslcc")
target("test")
    set_kind("binary")
    add_files("src/*.c)
    set_toolchains("@muslcc")

fetch the special version of clang

add_requires("clang 10.x")
target("test")
    set_kind("binary")
    add_files("src/*.c")
    set_toolchains("clang", {packages = {"clang", ...}})

fetch the special version of llvm

Full example: https://github.com/xmake-io/xmake/tree/dev/tests/projects/package/toolchain_llvm

add_requires("llvm 10.x", {alias = "llvm-10"})
target("test")
    set_kind("binary")
    add_files("src/*.c)
    set_toolchains("llvm@llvm-10")

fetch zig toolchain

Full example: https://github.com/xmake-io/xmake/tree/dev/tests/projects/package/toolchain_zig

add_requires("zig 0.8.x")
target("test")
    set_kind("binary")
    add_files("src/*.zig")
    set_toolchains("@zig")

fetch other compiler

add_requires("tinyc")
target("test")
    set_kind("binary")
    add_files("src/*.c")
    set_toolchains("@tinyc")

Switch to global cross-compilation toolchain for targets/packages

Full example: https://github.com/xmake-io/xmake/tree/dev/tests/projects/package/toolchain_muslcc

add_rules("mode.debug", "mode.release")

-- set cross-compliation platform
set_plat("cross")
set_arch("arm")

-- add toolchains package
add_requires("muslcc")

-- add library packages
add_requires("zlib", "libogg",  {system = false})

-- set global toolchains for target and packages
set_toolchains("@muslcc")

target("test")
    set_kind("binary")
    add_files("src/*.c")
    add_packages("zlib", "libogg")

[xq114]

This is really a nice feature! The version control of gcc et al. has been a problem on linux for long, since the compile process is too complicated for the most. Some system packages like update-alternatives lack many versions. Moreover, the conflict between system gcc and custom gcc is also a problem. See #1087

[waruqi]

This is really a nice feature! The version control of gcc et al. has been a problem on linux for long, since the compile process is too complicated for the most. Some system packages like update-alternatives lack many versions. Moreover, the conflict between system gcc and custom gcc is also a problem. See #1087

I have initially implemented this feature on the dev branch. And added llvm/llvm-mingw/muslcc/gnu-rm/zig toolchains to xmake-repo

if you want to see all examples, please see https://github.com/xmake-io/xmake/tree/dev/tests/projects/package

But because I don’t have much free time and the gcc toolchain is complicated, I haven’t added the gcc toolchain to xmake-repo.