[PATCH] CI: add SANITIZE=[address|undefined] jobs

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

Add CI targets for SANITIZE=address and SANITIZE=undefined. The former
would have caught a regression in 18bbc795fc5 (Merge branch
'gc/bare-repo-discovery', 2022-07-22) which made its way to
"master"[1].

Per [2] the GitHub fork of git.git runs with these in CI, so it's
already useful to some forks of this repository.

Also per [2] we could use SANITIZE=address with some ASAN_OPTIONS
instead of our SANITIZE=leak job added in 956d2e4639b (tests: add a
test mode for SANITIZE=leak, run it in CI, 2021-09-23), but unifying
those two with these new jobs would be a lot harder, so let's leave
that for now.

On my system a "make test" takes around 12m of user time,
SANITIZE=address around 44m, and SANITIZE=undefined around 18m.

In practice this doesn't seem to slow down the wallclock time of the
the GitHub CI by much This runs in about 50m, but getting through some
of the "win build" and associated tests can take around 40m, and the
"OSX" tests are on the order of 40m (all of this may vary with the
available workers etc.).

The "address" job will fail due to the issue reported in [1]. the
"undefined" one succeeds, but note that "t4058-diff-duplicates.sh"
triggers its assertions, they're just hidden by
"test_expect_failure" (see [3] for why).

1. https://lore.kernel.org/git/220725.861qu9oxl4.gmgdl@evledraar.gmail.com/
2. https://lore.kernel.org/git/YPClS0fj2HOJE5nH@coredump.intra.peff.net/
3. https://lore.kernel.org/git/cover-0.7-00000000000-20220318T002951Z-avarab@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---

This CI wil catch the memory corruption that made it to "master", see:
https://lore.kernel.org/git/220725.861qu9oxl4.gmgdl@evledraar.gmail.com/

 .github/workflows/main.yml | 6 ++++++
 ci/lib.sh                  | 6 ++++++
 2 files changed, 12 insertions(+)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index cd1f52692a5..4f59a7aa44c 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -251,6 +251,12 @@ jobs:
           - jobname: linux-leaks
             cc: gcc
             pool: ubuntu-latest
+          - jobname: SANITIZE=address
+            cc: gcc
+            pool: ubuntu-latest
+          - jobname: SANITIZE=undefined
+            cc: gcc
+            pool: ubuntu-latest
     env:
       CC: ${{matrix.vector.cc}}
       CC_PACKAGE: ${{matrix.vector.cc_package}}
diff --git a/ci/lib.sh b/ci/lib.sh
index f095519f8db..5ad60af2e7c 100755
--- a/ci/lib.sh
+++ b/ci/lib.sh
@@ -277,6 +277,12 @@ linux-leaks)
 	export SANITIZE=leak
 	export GIT_TEST_PASSING_SANITIZE_LEAK=true
 	;;
+SANITIZE=address)
+	export SANITIZE=address
+	;;
+SANITIZE=undefined)
+	export SANITIZE=undefined
+	;;
 esac
 
 MAKEFLAGS="$MAKEFLAGS CC=${CC:-cc}"
-- 
2.37.1.1107.g76fe5d1ed7c