[cdt-dev] managed make

[Bryan Hunt <bhunt@xxxxxxx>]

Since managed make seems to be a hot topic for discussion, I thought 
I'd add my $0.02.

When working on a very large project (~ 1,000,000 lines of code), we 
have found it very helpful to split the code into "modules".  In our 
case, our modules have a 1:1 correspondence with the sub-directories in 
the top level src directory.  They are combined into a single shared 
library and are typically compiled with optimization turned on.  If we 
need to debug, we will re-build a module with optimization turned off, 
and debug turned on, leaving the rest of the code optimized.  This can 
save us in compile, link, and execution time while debugging.

Another build technique we use is to create a module.all.C file that 
will #include each .C file in a module, then compile the module.all.C 
file into a single module.all.o file.  We have found this to greatly 
reduce link time, and the size of the shared library built (yes, it has 
drawbacks, but we live with that).

Just some food for thought.

Bryan