Instrumentation: Fuse gcov / ASan or split into independent builds (+ follow-up tests)?

  address-sanitizer, c++, g++, gcc, gcov

In my (linux-based) CI/CD pipeline i’m currently doing (basically):

  • Build Release (cmake out-of-source-build)
    • Test/(Custom-)Fuzz the build
  • Build Instrumentation-focused = gcov + ASan (again: cmake)
    • Test/(Custom-)Fuzz the build
    • Process Coverage (gcovr)

This is based on GCC 10 right now.

While thinking about adding Sonarqube-based analysis (which means using a build-wrapper which hopefully is as non-intrusive as described -> i even considered a 3rd build due to being somewhat scared!), i wondered about the original approach i have taken:

Is it safe / correct / a good idea to fuse the code-coverage and memory-sanitization instrumentation into a single build?

Is there any chance that i lose something (e.g. power of ASan-reasoning, coverage count accuracy, non-linear slowdowns) compared to independent builds (which sadly increases the time needed as we need to run the tests twice)?


For what it’s worth, a few more details on what it means using gcov/asan for me (yes: it’s not as clean as it could be in regards to other parts of the cmake-def):

# Code Coverage Analysis
option(ENABLE_CODE_COVERAGE_ANALYSIS "Enable instrumentalization-based code-coverage" OFF)
  message(STATUS "Instrumentalize for code-coverage analysis.")
  set(COV_LINKING gcov)

# ASAN Memory Sanitization
option(ENABLE_ASAN "Enable ASAN" OFF)
  message(STATUS "Instrumentalize for ASAN")
  set (CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -fno-omit-frame-pointer -fsanitize=address")
  set (CMAKE_LINKER_FLAGS_DEBUG "${CMAKE_LINKER_FLAGS_DEBUG} -fno-omit-frame-pointer -fsanitize=address")
  # suppress GRPC ASAN stuff

Source: Windows Questions C++