[Cdash] Problem with cdash, subprojects and CTEST_USE_LAUNCHERS=TRUE?

[Alexander Neundorf]

On Tuesday 21 August 2012, David Cole wrote:
> On Mon, Aug 20, 2012 at 5:23 PM, Alexander Neundorf <neundorf at kde.org>wrote:
> > On Monday 20 August 2012, Alexander Neundorf wrote:
> > > On Monday 20 August 2012, Alexander Neundorf wrote:
> > > ...
> > > 
> > > > I'm looking at it right now...
> > > > I actually haven't figured out yet how that launchers feature works.
> > > > Should the string "launch" (or "--launch") appear somewhere in the
> > > > buildtree as soon as I include CTest ?
> > > 
> > > Ah, wait, I got it: this happens in the testing build tree where cmake
> > > is executed from within ctest, right ?
> > 
> > Ok, here is a first try in the
> > ErrorIfCTEST_USE_LAUNCHERSSetButLauncherRuleNotSet branch on cmake stage.
> > 
> > It does now the following:
> > ~/src/CMake/tests/ltest/b$ /opt/cmake-HEAD/bin/cmake -
> > DCTEST_USE_LAUNCHERS=TRUE ..
> > -- Configuring done
> > CMake Error: CTEST_USE_LAUNCHERS is enabled, but the RULE_LAUNCH_COMPILE
> > global property is not defined.
> > Did you forget to include(CTest) in the toplevel CMakeLists.txt ?
> > ~/src/CMake/tests/ltest/b$
> > 
> > Alex
> 
> I think this should just be a warning. Do you think it's necessary to make
> it an error condition?

I wondered about this too.
My colleague spent quite some time trying to find the problem, and I also 
needed some time to find it.
So, I thought it might be a good idea to error out in the case, instead of 
"just" printing a warning and proceeding.

Not sure there is a use case for setting CTEST_USE_LAUNCHERS to TRUE but not 
including CTest.cmake, which is I think the only place where it is used.

OTOH, if somebody actually has a use for this, this patch would break his 
build...

Alex