[plt-scheme] mz-372 does not allow -O3 optimization

From: Filipe Cabecinhas (filcab at gmail.com)
Date: Wed Jun 11 17:05:10 EDT 2008


On 11 Jun, 2008, at 20:03, narutocanada at gmail.com wrote:

> I tried to compile mz-372 with -O3 optimization but failed,

You should be warned that -O3 has some dangerous optimizations which  
may even make the program slower (it unrolls more loops more  
aggressively (among other things) and will easily trash your  
instruction cache, making your program slower).

Normally you get the best results at -O2 or -Os (last time I checked - 
Os was a bit more unstable... But the Linux kernel is often built with  
-Os so it should be pretty stable).

As for the errors... You should check it with a debug utility (gdb,  
valgrind) to see where it blows up.

   - Filipe Cabecinhas

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