Add AddressSanitizer

Do not override the compilers (the CC and CXX environment variables).

Build libaom with sanitizer support using the -DSANITIZE=<type> cmake
option.

.github/workflows/ci-unix-static-sanitized.yml

@@ -11,11 +11,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest]
-        sanitizer: [ undefined ] # TODO(yguyon): Add address, memory, thread
-
-    env:
-      CC: clang
-      CXX: clang++
+        sanitizer: [ address, undefined ] # TODO(yguyon): Add memory, thread
 
     steps:
       - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
@@ -41,11 +37,10 @@ jobs:
       - name: Build aom
         if: steps.cache-ext.outputs.cache-hit != 'true'
         working-directory: ./ext
-        run: ./aom.cmd
-        env:
-          CFLAGS: -fsanitize=${{ matrix.sanitizer }}
-          CXXFLAGS: -fsanitize=${{ matrix.sanitizer }}
-          LDFLAGS: -fsanitize=${{ matrix.sanitizer }}
+        run: >
+          sed -i -e 's/cmake -G Ninja \(.*\) \.\./cmake -G Ninja \1 -DSANITIZE=${{ matrix.sanitizer }} ../g' aom.cmd
+
+          ./aom.cmd
       - name: Build dav1d
         if: steps.cache-ext.outputs.cache-hit != 'true'
         working-directory: ./ext
@@ -92,5 +87,6 @@ jobs:
         run: ninja
       - name: Run AVIF Tests
         working-directory: ./build
-        # ASAN_OPTIONS=allocator_may_return_null=1 may be necessary for address sanitizer.
         run: ctest -j $(getconf _NPROCESSORS_ONLN) --output-on-failure
+        env:
+          ASAN_OPTIONS: allocator_may_return_null=1