-----Original Message----- From:
address@hidden
[mailto:address@hidden org]
On Behalf Of David Brown Sent: Tuesday, December 23, 2008 9:24 AM
To: address@hidden Subject: [avr-libc-dev] Re: Add lib per
devide.
Have you tried using ccache? I haven't used it for compiling
avrgcc or avr-libc (I haven't recompiled these myself for ages -
the winavr package is too good!), but I've used it for other
compilations on both cygwin and linux.
You have to consider the type of project that avr-libc is. Avr-libc
is a library project, with many small modules that are written in
hand-optimized assembly, and built for many, many targets.
From looking at the website of ccache, it seems like it is a
preprocessor cache. There is very little preprocessing done on these
small assembly files. So I really don't see that ccache would be that
useful.
However, because this library is built for many targets (a lot more
so, if it were per device), the hierarchy of dependencies is not deep
but it is very wide, i.e. a lot of independent targets. When you have
a lot of independent targets, they can be built in parallel using
'make -j'. This is the reason for the large time savings in building
avr-libc.
If we built a library per device in avr-libc, I really don't worry
about how much time it takes. However, we should then have libgcc
built per device. Unfortunately, building gcc in parallel using 'make
-j' is problematic so it would take a lot of time building libgcc per
device.
Eric