ci(macos): build pip C extensions with Apple clang

python-ldap failed to link with 'ld: library ldap_r not found': the
Homebrew llvm@14 clang (on PATH for the analyzer) cannot link against the
current macOS SDK's .tbd libraries. Apple's clang handles the SDK
natively, so set CC/CXX to it for pip builds. The analyzer selects its
binary independently of $CC, so analysis still uses clang@14. Verified
locally that Apple clang links -lldap_r -llber against the SDK.

Author: gamesh411

.github/workflows/install-deps-macos.sh

@@ -56,4 +56,12 @@ if [ -n "$GITHUB_ENV" ]; then
   # (breaking analyze_and_parse's gcc tests). Pin the deployment target to the
   # SDK version so no override (and no warning) is emitted.
   echo "MACOSX_DEPLOYMENT_TARGET=$(xcrun --show-sdk-version)" >> "$GITHUB_ENV"
+  # Build pip C extensions (e.g. python-ldap) with Apple's clang, not the
+  # Homebrew llvm@14 clang that this script puts on PATH for the analyzer.
+  # clang@14 cannot link against the current macOS SDK's TBD libraries
+  # (e.g. 'ld: library ldap_r not found'), whereas Apple clang handles the
+  # SDK natively. CodeChecker selects its analyzer binary independently of
+  # $CC, so this does not affect which compiler is analyzed/used as analyzer.
+  echo "CC=/usr/bin/clang" >> "$GITHUB_ENV"
+  echo "CXX=/usr/bin/clang++" >> "$GITHUB_ENV"
 fi