Creating subdirs of distdir

[Stepan Kasal]

Hello,
  I have looked at how the subdirectories of distdir are created.
Let me sum up:

i) automake collects all subdirectories in variable DISTDIRS, and the
top level Makefile.in then contains:
        $(mkdir_p) %DISTDIRS%

ii) During `make dist', before each of the files is copied, the
corresponding subdirectory is created, using $(mkdir_p).  The comment
admits it's very slow, and explains this is necessary because the 
list of subdirectories may depend on AM_CONDITIONALs.

I have two proposals:

First is simple: during `make dist', changing $(mkdir_p) to
        test -d .. || $(mkdir_p) ..
would speed up things.
Patch attached.  Will you accept it?

As the second proposal, I have the radical idea of removing the
DISTDIRS computation completely.  It is simple, and with my proposed
patch, it calls mkdir only once for each subdirectory.

Yes, the DISTDIRS method is slightly more effective, but I don't
think it's worth the amount of code which is needed, and which would
be needed to fix this for conditionals.

What do you think?

Have a nice day,
        Stepan Kasal

automake-20060514-distdir.patch
Description: Text document