Add new feature to allow building ckb-std using clang as C compiler #339

	name: Rust

	on: [push, pull_request]

	jobs:
	build:

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v1
	- name: Checkout submodules
	run: git submodule update --init --recursive
	- name: Install Rust target
	run: rustup target add riscv64imac-unknown-none-elf
	- name: Install cross
	run: cargo install cross --git https://github.com/cross-rs/cross --rev=6982b6c
	- name: Build without riscv C compiler
	run: cargo build --target=riscv64imac-unknown-none-elf --no-default-features --features=ckb-types,allocator
	- name: Check example
	run: cross check --examples
	- name: Install capsule
	run: cargo install ckb-capsule --git https://github.com/nervosnetwork/capsule --rev 5c1b2ce
	- name: Run tests
	run: make test

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