Detailed guide on using gcov with CMake/CDash?

Question

I\'m using CMake with my project and set up a cdash server for continuous/nightly building. Everything works well and by setting up a crontab, we have hourly/nightly build/t

Answer 1

This answer is the same as @rcomblen's answer but its a bit outdated so I'll share my solution. Here's what I did:

1. created a toy project

(base) ciaran@DESKTOP-K0APGUV:/mnt/d/CoverageTest$ tree -L 2
.
├── CMakeLists.txt
├── cmake
│   └── CodeCoverage.cmake
├── src
│   ├── domath.cpp
│   ├── domath.h
│   └── testdomath.cpp
└── third_party
    └── googletest

Where

// src/domath.h

#ifndef COVERAGETEST_DOMATH_H
#define COVERAGETEST_DOMATH_H


class domath {

public:
    int add(int a, int b);
};


#endif //COVERAGETEST_DOMATH_H

and

// src/domath.cpp

#include "domath.h"

int domath::add(int a, int b) {
    return a + b;
}

and

// src/testdomath.cpp
#include "gtest/gtest.h"
#include "domath.h"


TEST(DoMathTests, testAdd){
    domath m;
    int actual = m.add(4, 6);
    ASSERT_EQ(10, actual);
}

2. download googletest and put it under third party directory
3. copy the gist so kindly shared by the other answers on this thread into cmake/CodeCoverage.cmake
4. install gcovr. This step is vital, because the other answers on this thread no longer work with the version of gcovr that I already had:

(base) ciaran@DESKTOP-K0APGUV:/mnt/d/CoverageTest$ pip install gcovr
(base) ciaran@DESKTOP-K0APGUV:/mnt/d/CoverageTest$ gcovr --version
gcovr 4.2
(base) ciaran@DESKTOP-K0APGUV:/mnt/d/CoverageTest$ which gcovr
/home/ciaran/miniconda3/bin/gcovr

Note, we need the output of which gcovr for the cmake script. 4) Write a cmake script that create a library, a test executable and use the CodeCoverage.cmake module:

cmake_minimum_required(VERSION 3.15)
project(CoverageTest)

set(CMAKE_CXX_STANDARD 14)

# setup googletest
add_subdirectory(third_party/googletest)

# create our library
add_library(DoMath STATIC src/domath.h src/domath.cpp)
add_dependencies(DoMath gtest gtest_main)

# create the test executable
add_executable(TestDoMath src/testdomath.cpp)
target_include_directories(TestDoMath PRIVATE third_party/googletest/googletest)
target_link_libraries(TestDoMath PRIVATE
        DoMath gtest gtest_main)
add_dependencies(TestDoMath DoMath gtest gtest_main)

# now for coverage bits
set(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake)
if (CMAKE_COMPILER_IS_GNUCXX)
    include(CodeCoverage)
    append_coverage_compiler_flags()

    # we need to turn off optimization for non-skewed coverage reports
    set(CMAKE_CXX_FLAGS  "${CMAKE_CXX_FLAGS} -O0")
    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -O0")

    # optional excludes - None needed here
    #    set(COVERAGE_EXCLUDES)

    # importantly, set the path to the gcovr executable that you downladed
    set(GCOVR_PATH "/home/ciaran/miniconda3/bin/gcovr")
    # Works
    setup_target_for_coverage_gcovr_xml(
            NAME TestDoMathCoverageXml
            EXECUTABLE TestDoMath
            DEPENDENCIES TestDoMath DoMath
    )
    # Works
    setup_target_for_coverage_gcovr_html(
            NAME TestDoMathCoverageHtml
            EXECUTABLE TestDoMath
            DEPENDENCIES TestDoMath DoMath
    )
    # This one did not work for me:
    setup_target_for_coverage_lcov(
            NAME TestDoMathCoverageLcov
            EXECUTABLE TestDoMath
            DEPENDENCIES TestDoMath DoMath
    )
endif ()

And thats it. Now just build the new targets.

Good luck.