Travis CI compiler errors not detected

[jay]

I did this

https://travis-ci.org/curl/curl/jobs/515938887#L6033

connect.c: In function ‘Curl_is_connected’:
connect.c:846:14: error: unused variable ‘buffer’ [-Werror=unused-variable]
         char buffer[STRERROR_LEN];
              ^~~~~~
connect.c: In function ‘tcpnodelay’:
connect.c:902:8: error: unused variable ‘buffer’ [-Werror=unused-variable]
   char buffer[STRERROR_LEN];
        ^~~~~~

...

cc1: all warnings being treated as errors
make[2]: *** [libcurl_la-connect.lo] Error 1
make[2]: Leaving directory `/home/travis/build/curl/curl/lib'
make[1]: *** [all] Error 2
make[1]: Leaving directory `/home/travis/build/curl/curl/lib'
make: *** [all-recursive] Error 1

...

Done. Your build exited with 0.

#10260.5 passed

I expected the following

#10260.5 errored

[bagder]

Weird! I can't see that we've changed anything to make this stop working... ?

[webmaster128]

There is an endless debate about Travis status code handling and fast failing of scripts, e.g. in this thread about set -e in .travis.yml. At lot of those problems are a result of Travis composing a single bash script out of everything in .travis.yml plus their own setup. In my experiance the only thing that works reliably is calling a main travis bash script as the only step in script. In that main script, set -o errexit -o nounset -o pipefail can be used independent of the surrounding shell context to harden the execution.

Nice to have: custom output folding can be done using custom fold_start/fold_end functions (which requires exposing some Travis internals) in the custom shell script (like this).

[jay]

Alright let's try that. Please review PR #3755 and let me know what I did wrong because I'm sure there will be something.

[webmaster128]

For the fast failing issue also see travis-ci/travis-ci#1066

[bagder]

I propose we just drop this issue as this is not a major concern and nobody seems to work on it?

[jay]

Resurrected