Confusing errors when a subprojects fails in Visual Studio

[traversaro]

When a subproject fails when compiling the superbuild in Visual Studio, a cryptic error is printed, instead of the actual output of the command that failed (and differently from how make behaves).

In those case the best way to debug the problem is to run CMake for the subproject (if the failure was during configuration/generation) or directly the solution of the subproject (if the failure was during compilation): however this operation is not obvious for new users of the superbuild.

It would be nice to check if something could be changed in robotology-superbuild or YCM or CMake's ExternalProject ot the CMake's source code to change this (I am afraid the latter is necessary).

[traversaro]

cc @claudia-lat

[traversaro]

@hu-yue and @GiulioRomualdi were the last two users tricked by this.

[traversaro]

@GiulioRomualdi and @kouroshD were also affected by this. For the sake of finding this issue, the actual error that is printed by Visual Studio when executing the superbuild that it fails is:

MSB6006 "cmd.exe" exited  with error code 1