Check if an entry in the TLS callback list is the terminator before trying to load it #484

	name: CI
	on:
	push:
	pull_request:
	branches:
	- master

	jobs:
	test:
	name: Test
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	build: [MSRV, stable, nightly, macos, win32, win64]
	include:
	- build: MSRV # Minimum supported Rust version
	os: ubuntu-latest
	rust: 1.63.0
	- build: stable
	os: ubuntu-latest
	rust: stable
	- build: nightly
	os: ubuntu-latest
	rust: nightly
	- build: macos
	os: macos-latest
	rust: stable
	- build: win32
	os: windows-latest
	rust: stable-i686-msvc
	- build: win64
	os: windows-latest
	rust: stable-x86_64-msvc
	env:
	CARGO_TARGET_DIR: ${{ github.workspace }}/target
	steps:
	- uses: actions/checkout@master
	- name: Cache CARGO_HOME
	uses: actions/cache@v1
	with:
	path: ~/.cargo
	key: ${{ runner.os }}-cargo-home-${{ hashFiles('**/Cargo.toml') }}
	restore-keys: ${{ runner.os }}-cargo-home
	- name: Install Rust
	shell: bash
	run: \|
	curl -sSL https://sh.rustup.rs \| sh -s -- -y --profile=minimal --default-toolchain=none
	export PATH="$HOME/.cargo/bin:$PATH"
	rustup override set ${{ matrix.rust }}
	echo "$HOME/.cargo/bin" >> $GITHUB_PATH
	- name: rustfmt
	shell: bash
	if: runner.os == 'Linux' && matrix.rust == 'stable'
	run: \|
	rustup component add rustfmt
	cargo fmt -- --check
	- run: cargo build
	- run: cargo build --all-targets
	# FIXME: Looks like fuzzer cannot be run on Windows
	- if: runner.os == 'Linux'
	run: cargo build --manifest-path=fuzz/Cargo.toml
	- run: cargo test
	- run: make api

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