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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Monday 03 Mar 2003 8:14 pm, Andrew Rogers wrote: > A friend has compiled his program on both GCC 2.96 and MS Visual C++ (I > don't know which release). He claims that Visual C++ gives a two fold > speed increase to his program. As I did not want to believe this I set > about investigating the cause of this apparent speed increase. The > program was compiled on Visual C++ as 'release', I don't have Visual > C++, but presumably this means that there is no debugging info in the > executables. When I looked at the executable produced by GCC there seems > to be alot of debugging stuff in the executable file. I suspect that > this debugging info is causing the slower execution of the GCC compiled > version. I can't seem to find a way to remove this debugging info and > there are no -g switches in my GCC command line. Have you tried $ strip progfile ? man strip strip - Discard symbols from object files. > > Is there any way to have GCC not output the debugging info? Usually strip is called as part of the 'release' package - say RPM - or via the Makefile. > Slighty seperate issue, I compiled a program with -O3 (optimisation) on > both GCC 2.96 and GCC 3.2 but they both execute at exactly the same > speed. I thought that GCC 3.2 had significantly improved optimisation. Don't most optimisations depend on the program itself actually implementing suitable functions and operations? Also, are you comparing like with like? Visual C++ (as Borland C++ and others) often relies on DLL's to code most of the work so the executable will be smaller. If both programs are statically linked, you may find a reversal in file size and perhaps speed. Dynamically linked libraries DO count as part of the overall application size whatever the compiler/OS - just look at the problems with some VBrun dll's and RPM dependency problems. - -- Neil Williams ============= http://www.codehelp.co.uk http://www.dclug.org.uk http://www.wewantbroadband.co.uk/ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.7 (GNU/Linux) iD8DBQE+Y9LriAEJSii8s+MRAl7KAKDJ85MSv3YJmzessS921aHY3q6XogCfdQS4 7RvDFajOnnLBCuG1GgWKarU= =7g/0 -----END PGP SIGNATURE----- -- The Mailing List for the Devon & Cornwall LUG Mail majordomo@xxxxxxxxxxxx with "unsubscribe list" in the message body to unsubscribe.