Add address/undefined behavior/thread sanitizer builds to CI

[peddie]

This PR fixes existing runtime sanitizer failures and then adds CI jobs to run the sanitizers on every PR.

[peddie]

This cannot be merged for two reasons:

• Part of Use swift_add_tool() for unit test suite #374 fixes an error that prevents clang-14 from building
• The address and thread sanitizers both fail due to Possible heap memory error in group-by code #372
  • I cannot mask the failure at the function level because function attributes do not seem to work when applied to templated functions, and the test case that fails is a TYPED_TEST_P, so it's impractical to even pull out the failing bit into a separate function that I can annotate instead.

[peddie]

I've addressed the issues I mentioned above; it's ready for review.

[akleeman]

lgtm!

[akleeman]

curious why auto doesn't work here?

[peddie]

It deduces a reference type which has lifetime issues, triggering the address sanitizer!

[john-michaelburke]

extreme nit. This and the address undefined leak jobs are relatively similar so we can matricize them. Something like:

Suggested change

	ubuntu-clang14-thread:
	runs-on: ubuntu-22.04
	steps:
	- name: Checkout source
	uses: actions/checkout@v2
	with:
	submodules: recursive
	ssh-key: ${{ secrets.SSH_KEY }}
	- name: Install clang-14
	run: |
	sudo apt-get update && \
	sudo apt-get install build-essential software-properties-common -y && \
	sudo add-apt-repository ppa:ubuntu-toolchain-r/test -y && \
	sudo apt-get update && \
	sudo apt-get install clang-14 && \
	gcc -v
	- name: Run build
	env:
	CC: clang-14
	CXX: clang++-14
	TESTENV: clang14
	run: |
	bash ./ci/run_thread_sanitizer_tests.sh
	ubuntu-clang14-sanitizer-tests:
	runs-on: ubuntu-22.04
	strategy:
	os:
	- { name: "address-undefined-leak", script: "./ci/run_address_sanitizer_tests.sh" }
	- { name: "thread", script: "./ci/run_thread_sanitizer_tests.sh" }
	steps:
	- name: Checkout source
	uses: actions/checkout@v2
	with:
	submodules: recursive
	ssh-key: ${{ secrets.SSH_KEY }}
	- name: Install clang-14
	run: |
	sudo apt-get update
	sudo apt-get install build-essential software-properties-common -y
	sudo add-apt-repository ppa:ubuntu-toolchain-r/test -y
	sudo apt-get update
	sudo apt-get install clang-14
	gcc -v
	- name: Run (${{ matrix.name }} ) Sanitizer Tests
	env:
	CC: clang-14
	CXX: clang++-14
	TESTENV: clang14
	run: |
	bash "${{ matrix.script }}"

[peddie]

Done; let's see if I copied correctly :)

[john-michaelburke]

We might be able to replace this with a premade action, such as:
https://github.com/marketplace/actions/install-llvm-and-clang

Maybe in a separate PR.

[peddie]

Feel free to make a ticket for the future -- for now I think I'll just keep it simple.