gdb testsuite

[Jim Blandy]

It's not obvious to me where the -lm comes from.  gdb/testsuite/lib
contains a number of files that are also involved in running the
tests; in particular, gdb_compile is defined in
gdb/testsuite/lib/gdb.exp.

One unfortunate characteristic of the GDB test suite is that, even if
GDB is horribly broken, many tests will still pass.  You can't have
much confidence that things are basically working with 356 failures.
You should look through gdb.log and work through a bunch of them to
get a feel for the state of things.

If you're going to do any significant amount of work with the test
suite, I would recommend investing a little time in learning the Tcl
language.  It's built on some very simple concepts, and knowing how
those actually work, instead of guessing based on the resemblance
between Tcl and more familiar languages, will save confusion in the
future.  I think there are tutorials on-line somewhere.