RFC: new debug option "--debug=c" which echoes all commands executed

[R. Bernstein]

Bill Cox writes:
 > Hi Folks,
 > 
 > I'd like to propose, and implement, a new option that would
 > help debug a deep Makefile tree by echoing *all* of the commands
 > that the Makefiles executed, even if the "-s" option or
 > the .SILENT pseudo-target is coded, or if the command line
 > begins with an "@" sign.

It has been asked for proposed before and I think it got a favorable
response last time it came up. Well, actually now that I think of it I
may have brought it up and maybe someone said that was all that was
needed ;-)

I have a version of GNU make which adds this kind of tracing and also
interactive debugging (and better error reporting). The source tarball
for the last CVS version is here:

  http://bashdb.sourceforge.net:/remake-3.80+dbg-0.3cvs.tar.gz

and ViewCVS is here: 
  http://cvs.sourceforge.net/viewcvs.py/bashdb/remake/

our you can find it off of the bashdb project on sourcforge.

("bashdb" is a debugger for bash - another project where debugging was
conspicously lacking for a long time.)

In the debugger-enable make, "remake" the option to use is -x, the
same as you would do for a POSIX shell. The long option is
--trace. And to enter the debugger you enter --debugger or
--debugger=TYPE where TYPE is one of "enter", "full", "error", or
"fatal". (You don't type the quotes.)

I'll say that this code is far from flawless or far from complete. But
I've found it very useful and helpful in tracking down Makefile
problems.