Re: Bogus reports from coverage.postgresql.org

Tom Lane wrote:

> Well, this is darn interesting.  I got the Fedora lcov maintainer
> to push an update absorbing the upstream "gcc 8" fixes.  (Turned
> out he'd already done that for rawhide, but forgot to push it into
> the F28 branch.)  And with that, and gcc 8.0.1, ... no bug.  The
> lines are marked "lineNoCov" with or without lcov_branch_coverage.

Hmm.  I wonder if this means that the reports generated with any
compiler prior to gcc 8 are unreliable.  At least we know now that that
is indeed the case with branch coverage, but what about without?

While we're on this topic ...  Some time ago, I looked into whether it
would be possible to make the coverage report ignore the elog(ERROR)
lines, which are --or should be-- unreachable code and thus we don't
care too much about test coverage.  Finding no way to implement that, I
gave up (I tried adding exclusion markers in the elog definition, as
documented in geninfo.  Perhaps I did it wrong).  But maybe it is
possible with these recent improvements?

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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