One potential drawback to using a derived-file cache is that the output printed by SCons can be inconsistent from invocation to invocation, because any given file may be rebuilt one time and retrieved from the derived-file cache the next time. This can make analyzing build output more difficult, especially for automated scripts that expect consistent output each time.

If, however, you use the --cache-show option, SCons will print the command line that it would have executed to build the file, even when it is retrieving the file from the derived-file cache. This keeps the build output consistent across builds:

% scons -Q
cc -o hello.o -c hello.c
cc -o hello hello.o
% scons -Q -c
Removed hello.o
Removed hello
% scons -Q --cache-show
cc -o hello.o -c hello.c
cc -o hello hello.o

The trade-off, of course, is that you no longer know whether or not SCons has retrieved a derived file from cache or has rebuilt it locally.