[PATCH 2/2] travis-ci: fail if Coccinelle static analysis found something to transform

Coccinelle's and in turn 'make coccicheck's exit code only indicates that Coccinelle managed to finish its analysis without any errors (e.g. no unknown --options, no missing files, no syntax errors in the semantic patches, etc.), but it doesn't indicate whether it found any undesired code patterns to transform or not. To find out the latter, one has to look closer at 'make coccicheck's standard output and look for lines like:

  SPATCH result: contrib/coccinelle/<something>.cocci.patch

And this only indicates that there is something to transform, but to see what the suggested transformations are one has to actually look into those '*.cocci.patch' files.

This makes the automated static analysis build job on Travis CI not particularly useful, because it neither draws our attention to Coccinelle's findings, nor shows the actual findings. Consequently, new topics introducing undesired code patterns graduated to master on several occasions without anyone noticing.

The only way to draw attention in such an automated setting is to fail the build job. Therefore, modify the 'ci/run-static-analysis.sh' build script to check all the resulting '*.cocci.patch' files, and fail the build job if any of them turns out to be not empty. Include those files' contents, i.e. Coccinelle's suggested transformations, in the build job's trace log, so we'll know why it failed.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
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 ci/run-static-analysis.sh | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)