# submit to CDash with excluding lines from coverage using GCOV\_EXCL\_LINE

**URL:** https://discourse.cmake.org/t/submit-to-cdash-with-excluding-lines-from-coverage-using-gcov-excl-line/1259
**Category:** Usage
**Tags:** os:linux, gen:makefiles
**Created:** [May 23, 2020, 9:05am UTC](https://discourse.cmake.org/t/submit-to-cdash-with-excluding-lines-from-coverage-using-gcov-excl-line/1259 "2020-05-23T09:05:26Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![Nikhil\_Reddy\_Ramolla](https://discourse.cmake.org/user_avatar/discourse.cmake.org/nikhil_reddy_ramolla/32/611_2.png) [@Nikhil\_Reddy\_Ramolla](https://discourse.cmake.org/u/Nikhil_Reddy_Ramolla)
#### Post date: [May 23, 2020, 9:05am UTC](https://discourse.cmake.org/t/submit-to-cdash-with-excluding-lines-from-coverage-using-gcov-excl-line/1259/1 "2020-05-23T09:05:26Z")

</div>

Hello all,  
I am learning CMake by making a sample C++ project, and I have succesfully integrated it with CDash, with both tests (using boost unit test) and coverage (using --coverage and gcov). I am using this CTest  
Script to submit to CDash:

```
set(CTEST_SOURCE_DIRECTORY ${CTEST_SCRIPT_DIRECTORY}/src)
set(CTEST_BINARY_DIRECTORY ${CTEST_SCRIPT_DIRECTORY}/bin)
include(${CTEST_SOURCE_DIRECTORY}/CTestConfig.cmake)
set(CTEST_CMAKE_GENERATOR "Unix Makefiles")
set(CTEST_COVERAGE_COMMAND gcov)
ctest_empty_binary_directory(${CTEST_BINARY_DIRECTORY})
ctest_start(Experimental)
ctest_configure()
ctest_build()
ctest_test()
ctest_coverage()
ctest_submit()

```

> gcc coverage flags are not written in the above script because CMakeLists.txt contains coverage flags by default, as this is a sample project

However, I would like to exclude specific lines in each source file using GCOV\_EXCL\_LINE, GCOV\_EXCL\_START, and GCOV\_EXCL\_STOP, which is not happening with gcov.

I have looked at alternatives and found lcov, which takes the files generated by gcov and converts it into a .info file, which is then converted into a coverage report with genhtml. It is successfully excluding lines with GCOV\_EXCL\_LINE in the generated html file, but when I replace it with CTEST\_COVERAGE\_COMMAND in the script (in hopes of integrating it with CDash, instead of a html coverage report), it is throwing some errors, probably because it is not intended to use in such a manner. this is an output from `ctest -VV -S run_experimental.cmake` :

```
.lcov -o /path/to/testThis.dir /path/to/testThis.dir/this.cpp.gcda
lcov: Need one of options -z, -c, -a, -e, -r, -l, --diff or --summary
Use lcov --help to get usage information
Coverage command returned: 2 while processing: /path/to/testThis.dir/this.cpp.gcda
Command produced error: 0

```

Another way I tried to fix this thing is to use a wrapper around gcov which will exclude all required lines in the files generated by gcov.

Add this line to ctest script:

```
set(CTEST_COVERAGE_COMMAND ${CTEST_SCRIPT_DIRECTORY}/gcovw)

```

This is gcovw:

```
#!/usr/bin/env python3
import re, subprocess, sys

if len(sys.argv) < 2:
    exit(1)
else:
    process = subprocess.Popen(
        ['/usr/bin/gcov'] + sys.argv[1:],
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE
    ) 
    
    out,err = process.communicate()
    process.wait()
    out,err = out.decode(),err.decode()
   
    if (process.returncode != 0) or (err != ''):
        print(out, end='')
        print(err, end='', file=sys.stderr)
        exit(process.returncode or 1)
    else:
        files = [x.group(1) for x in re.finditer('^Creating \'([^\']*)\'$', out, flags=re.MULTILINE)]
        regex = re.compile(r'^[^:]*:(.*[GL]COVR?_EXCL_LINE.*)$', flags=re.MULTILINE)
        for _file in files:
            fp = open(_file, 'r')
            data = fp.read()
            data = regex.sub(' -:\g<1>', data)
            fp.close()
            fp = open(_file, 'w')
            fp.write(data)
            fp.close()
        print(out, end='')

```

Although it works, I think this is a bit hacky, and I want a more elegant solution:

1. Enable GCOV\_EXCL\_LINE in gcov (if it’s possible)
2. Some other tool which can do this (needs to exclude GCOV\_EXCL\_LINE and should be able to show the coverage on cdash)

Could you show me how?