Tony Peden wrote:
 > I've done some experiments with inlining this morning.  First I
 > blindly removed all of the inline keywords from all JSBSim headers,
 > then compiled with -O2 -fno-default-inline. For the c172 in a 300 sim
 > second run of steady-level flight following a trim, this required
 > right at 3 seconds.

How about compile time?  I've been meaning to bug you about this. :)

The new version of FGState.cpp, as checked in a few days ago, takes
five (!) minutes to build on my machine.  Yikes.  The whole of JSBSim
is running well over 15 minutes of compile time now.  Turning off
optimization, or simply adding the -fno-inline switch, essentially
fixes the problem and the build takes a few seconds per file.

I looked briefly at the code, and I'm not sure it's easy to fix.  The
inlined stuff looks, to me, like a bunch of vector<> operations
inlined from the standard library headers.  The structure of the file
is such that there are a lot of them, but the inlining really isn't
something you can control directly.

What I've done is simply disable optimization for the JSBSim directory
by hacking at the Makefile's CFLAGS definition.  But we really need to
get this under control.  Is no one else as annoyed by our build times
as I am?  Is it possible that the JSBSim from CVS builds without
optimization and that therefore the core developers aren't aware how
slow things are for those building from the FlightGear tree?

Andy

-- 
Andrew J. Ross                NextBus Information Systems
Senior Software Engineer      Emeryville, CA
[EMAIL PROTECTED]              http://www.nextbus.com
"Men go crazy in conflagrations.  They only get better one by one."
  - Sting (misquoted)


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