Build of examples fails if part of path is a softlink

[rael007]

Build of examples fails if part of path is a softlink

[cesaro]

I'm also hitting this issue. The problem is that --no-external incorrectly filters out files when they can be accessed via symbolic links.

Here is a simple script that reproduces the problem, in a format that should be easy to adapt for the regression tests, @henry2cox:

#!/bin/bash
set -xe

mkdir -p /tmp/bug
cd /tmp/bug

rm -Rf src src2

mkdir src
ln -s src src2

echo 'int a (int x) { return x + 1; }' > src/a.c
echo 'int b (int x) { return x + 2; }' > src/b.c

gcc -c --coverage src/a.c -o src/a.o
gcc -c --coverage src2/b.c -o src/b.o

lcov -o out -c -i --no-external -d src

You would expect that the call to lcov -c -i records the coverage of both a.c and b.c, but --no-external is incorrectly dropping b.c:

+ lcov -o out -c -i --no-external -d src
Capturing coverage data from src
geninfo cmd: '/path/to/geninfo src --output-filename out --initial --no-external'
Found gcov version: 12.3.0
Using intermediate gcov format
geninfo: WARNING: (usage) branch filter enabled but branch coverage not enabled
        (use "geninfo --ignore-errors usage,usage ..." to suppress this warning)
Recording 'internal' directories:
        /tmp/bug/src
Writing temporary data to /tmp/geninfo_datHcWj
Scanning src for .gcno files ...
Found 2 graph files in src
using: chunkSize: 1, nchunks:2, intervalLength:0
Dropping 'external' file '/tmp/bug/src2/b.c'
Finished processing 2 GCNO files
Excluded data for 1 file due to include/exclude options
Apply filtering..
Finished filter file processing
Finished .info-file creation
Summary coverage rate:
  source files: 1
  lines.......: 0.0% (0 of 1 line)
  functions...: 0.0% (0 of 1 function)
Message summary:
  1 warning message:
    usage: 1

And this is probably happening because /tmp/bug/src/b.gcno refers to the path that uses symbolic links:

$ strings /tmp/bug/src/b.gcno
oncg*32B
/tmp/bug
src2/b.c
src2/b.c
src2/b.c

and because lcov --no-external doesn't canonicalize file path names (see realpath(1)) before comparing them.

[henry2cox]

Hi -
Thanks for the testcase.
I actually think there is about an even chance that a user would want to include symlinked out-of-tree files and directories, or would want to exclude them - and an even better chance that (s)he would want to include some and exclude others.

In any case, I updated the man pages to note that --no-external is a bit of a blunt instrument, and that --include, --exclude can provide finer-grained control when --no-external fails to do what you want - and also added an option (really, re-used an existing option) to select how symlinked directories are treated.
I will push the update shortly.

Henry

[henry2cox]

fix pushed in 2efc0fb

[henry2cox]

Closing this issue as I believe it is fixed in commit listed above.
If there is still a problem, please reopen this issue or file a new one.
Please include a testcase and/or recipe to reproduce the problem.
Henry