runtest gdb testsuite oddities.

[Joel Brobecker]

> Toms check-in today regarding the failure in py-infthread.exp had me
> exploring why I did not see it.  For some reason when one runs: runtest
> gdb.python/*.exp the testsuite seems to pass just fine.  But when one
> runs just one (failing) exp file, the test fails as it should.  I'm not
> sure why, and my fu regarding dejagnu is very slim.  Can anyone explain
> what is going on here?  Hopefully it is something silly I have done. 

Each testcase (.exp) is actually part of the same run.  When you think
of scripts being executed, they are actually files being sourced.
So what I am thinking happened to you is that, in your normal context,
you first "ran" (in other words: sourced) a gdb.python testcase that
called "load_lib gdb-python.exp", and thus defined the
gdb_py_test_silent_cmd procedure.  "Thanks" to that, by the time dejagnu
"ran" py-infthread.exp, tcl/expect could find gdb_py_test_silent_cmd,
even though the "script" is missing a call to load_lib.

-- 
Joel