[vtk-developers] Dashboards

[Ken Martin]

OK I'm not going to send a long email (but after edits it is long) but just
one short note. After checking in code, please check the dashboard the next
couple of days for warnings or errors. (I'm not even going to address tests
here) Please be aware of some common pitfalls:

1) The "I gotcha" pitfall: Finding one compiler warning or error on one
platform feels really good and sometimes while celebrating you can forget to
look at the other 40 platforms. I suggest making bug fix celebrations more
intense but of a shorter duration so as to not lose focus.

2) The closely related "I bet it is the same warning on all platforms bug"
it turns out that each compiler has it own mysterious drand48 based warning
generator. When two dashboard entries have problems there is no guarantee
they are the same without actually looking at them. Think of it as a game of
"Go Fish"

3) The "whoa, that's way too much yellow and red, I must avert my eyes"
pitfall. This is a tough one. Sometimes the dashboard is just hard to look
at. You wonder if it is a testbed for some form of hardware splatting based
on ketchup and mustard. In this case I suggest looking at a couple platforms
to see if anything looks like it is related to your checkins. If not then
wait until the next day to contemplate the dashboard. (this only applies to
really messed up dashboards not the normal run-of-the-mill mess)

4) The "that's a warning in std::stream so it cannot be because of my recent
checkins" pitfall. Compiler vendors sometimes like to obfuscate warnings to
see how confused they can make programmers. There are two solutions to this
problem. The first is to be nice to compiler writers to reduce their overall
level of anger. The second is to look at the file being compiled. This is
typically a few lines above the warning and frequently the warning is due to
something in that class. Your code may be completely valid ANSI C++. But
odds are that the warning can be fixed by small changes in your code. Look
at other classes in VTK that do the same thing or use the same class.

5) The "the compile warning line is too long to fit on my screen" pitfall.
I've got two words for you "horizontal scrollbar" Most browsers support
vertical scrolling without loosing the horizontal scroll position.

6) The "I can't fix my classes' errors on the dashboard, I barely had enough
time to check in that class" pitfall. There are two options here. The
easiest is to wait until you have time to do it correctly before checking in
a class. The other involves having Wesley and Geordie create more time using
a tricorder, some dilythium shavings, and a sacrificial tribble.


I've probably forgotten a few other classics and I am certainly guilty of
all of these at one point or another (except the thing with the tribble).
I'm working hard to get some of the longstanding warnings and errors cleaned
up so hopefully this process will be easier in the future.

Thanks
Ken


Ken Martin, PhD
Kitware Inc.
518 371 3971 x101
469 Clifton Corporate Pkwy
Clifton Park NY 12065