docs: document Android coverage limitation

After extensive testing, Swift Android's profraw files cannot be
processed by any available llvm-cov tool:

- Host Swift nightly llvm-cov: "bad magic" error
- Android NDK llvm-cov: LLVM version mismatch
- Swift toolchain llvm-cov: "bad magic" error (already tried)

This appears to be a fundamental incompatibility with Swift for
Android's coverage instrumentation. The profraw format generated
in the Android environment is unreadable by all available tools.

Solution:
- Continue collecting profraw files as artifacts
- Skip Codecov upload for Android
- Document as known limitation

The profraw files are preserved in artifacts for future investigation
when Swift Android tooling improves.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <[email protected]>

Author: leogdion

.github/actions/swift-android-action/action.yml

@@ -599,28 +599,8 @@ runs:
           echo "  fi" >> ${SCRIPT_FILE}
           echo "done" >> ${SCRIPT_FILE}
 
-          # Convert profraw to LCOV using Swift toolchain's llvm-cov (same nightly version)
-          echo "echo '==> Converting profraw to LCOV format...'" >> ${SCRIPT_FILE}
-          echo "if [ -f '${COVERAGE_DIR}/default.profraw' ]; then" >> ${SCRIPT_FILE}
-          echo "  # Find the test binary" >> ${SCRIPT_FILE}
-          echo "  TEST_BINARY=\$(find \${SWIFT_SDK_TARGET}/debug -name '*.xctest' | head -n 1)" >> ${SCRIPT_FILE}
-          echo "  if [ -n \"\$TEST_BINARY\" ]; then" >> ${SCRIPT_FILE}
-          echo "    # Use Swift toolchain's llvm-cov (matches the Swift compiler that generated profraw)" >> ${SCRIPT_FILE}
-          echo "    SWIFT_LLVM_COV=\"\${SWIFT_INSTALLATION}/bin/llvm-cov\"" >> ${SCRIPT_FILE}
-          echo "    if [ -f \"\$SWIFT_LLVM_COV\" ]; then" >> ${SCRIPT_FILE}
-          echo "      \"\$SWIFT_LLVM_COV\" export -format=lcov -instr-profile='${COVERAGE_DIR}/default.profraw' \"\$TEST_BINARY\" > '${COVERAGE_DIR}/coverage.lcov' 2>&1 && {" >> ${SCRIPT_FILE}
-          echo "        echo \"Successfully converted profraw to LCOV\"" >> ${SCRIPT_FILE}
-          echo "      } || {" >> ${SCRIPT_FILE}
-          echo "        echo \"Warning: Failed to convert profraw to LCOV\"" >> ${SCRIPT_FILE}
-          echo "        echo \"Keeping profraw file for artifact upload\"" >> ${SCRIPT_FILE}
-          echo "      }" >> ${SCRIPT_FILE}
-          echo "    else" >> ${SCRIPT_FILE}
-          echo "      echo \"Warning: Swift llvm-cov not found at \$SWIFT_LLVM_COV\"" >> ${SCRIPT_FILE}
-          echo "    fi" >> ${SCRIPT_FILE}
-          echo "  else" >> ${SCRIPT_FILE}
-          echo "    echo \"Warning: Test binary not found\"" >> ${SCRIPT_FILE}
-          echo "  fi" >> ${SCRIPT_FILE}
-          echo "fi" >> ${SCRIPT_FILE}
+          echo "echo '==> NOTE: profraw files from Swift Android cannot be processed by llvm-cov'" >> ${SCRIPT_FILE}
+          echo "echo '==> Files saved to artifacts for investigation'" >> ${SCRIPT_FILE}
 
           # List retrieved files for verification
           echo "echo '==> Coverage files retrieved:'" >> ${SCRIPT_FILE}

.github/workflows/MistKit.yml

@@ -173,16 +173,10 @@ jobs:
           collect-coverage: true
           coverage-output-dir: .build/coverage-android
 
-      - name: Upload coverage to Codecov
-        if: success() && hashFiles('coverage-android/coverage.lcov') != ''
-        uses: codecov/codecov-action@v4
-        with:
-          fail_ci_if_error: false
-          flags: android-api34-swift-nightly
-          verbose: true
-          token: ${{ secrets.CODECOV_TOKEN }}
-          files: coverage-android/coverage.lcov
-          # LCOV file generated by Android NDK's llvm-cov (matches Android clang version)
+      # Note: Android coverage cannot be uploaded to Codecov due to Swift Android tooling limitations
+      # The profraw files cannot be processed by any available llvm-cov (host, NDK, or Swift toolchain)
+      # All attempts result in "bad magic" or "version mismatch" errors
+      # Keeping profraw files as artifacts for future investigation
 
       - name: Upload Android coverage files as artifact
         if: always()