[PATCH v2] Add coverage target

[Dmitry V. Levin]

On Tue, Jan 12, 2021 at 12:48:17PM +0100, Mark Wielaard wrote:
> On Tue, 2021-01-12 at 07:29 +0300, Dmitry V. Levin wrote:
> > Implement a target for capturing code coverage using lcov.
> > It is available when elfutils is configured using --enable-gcov.
> 
> Very nice.
> 
> > +$(COVERAGE_OUTPUT_INDEX_HTML): $(COVERAGE_OUTPUT_FILE)
> > +	LC_ALL=C $(GENHTML) \
> > +		--legend \
> > +		--show-details \
> > +		--rc=genhtml_branch_coverage=1 \
> > +		--title='$(COVERAGE_TITLE)' \
> > +		--prefix='$(abspath $(abs_srcdir))' \
> > +		--prefix='$(abspath $(abs_builddir)/..)' \
> > +		--output-directory='$(COVERAGE_OUTPUT_DIRECTORY)' \
> > +		$<
> 
> Now that it is a top-level target the buildir /.. can be removed.
> Also depending on how I build there seems to be a combination of
> absolute and real paths in the coverage files (I have symlinks in my
> src and build dirs to make them go on separate disks). So I am using
> both:

If $(srcdir) != $(builddir), then there is a collision between
$(srcdir)/libcpu and $(builddir)/libcpu, so if we strip both $(abs_srcdir)
and $(abs_builddir) prefixes, we'll lose coverage in either $(srcdir)/libcpu
or $(builddir)/libcpu.

> diff --git a/Makefile.am b/Makefile.am
> index 30f763a9..69edcb02 100644
> --- a/Makefile.am
> +++ b/Makefile.am
> @@ -79,8 +79,10 @@ $(COVERAGE_OUTPUT_INDEX_HTML):
> $(COVERAGE_OUTPUT_FILE)
>                 --show-details \
>                 --rc=genhtml_branch_coverage=1 \
>                 --title='$(COVERAGE_TITLE)' \
> +               --prefix='$(realpath $(abs_srcdir))' \
>                 --prefix='$(abspath $(abs_srcdir))' \
> -               --prefix='$(abspath $(abs_builddir)/..)' \
> +               --prefix='$(realpath $(abs_builddir))' \
> +               --prefix='$(abspath $(abs_builddir))' \
>                 --output-directory='$(COVERAGE_OUTPUT_DIRECTORY)' \
>                 $<
> 
> Make that makes sense? Either way feel free to push this.

I'll test the following variant:

	--prefix='$(abspath $(abs_srcdir))' \
	--prefix='$(realpath $(abs_srcdir))' \
	--prefix='$(abspath $(abs_builddir)/..)' \
	--prefix='$(realpath $(abs_builddir)/..)' \


-- 
ldv