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2.4 CC Optimizations

When using the C compiler to compile the C code output by hobbit, always use strong optimizations (eg. ‘cc -xO3’ for cc on Sun, ‘gcc -O2’ or ‘gcc -O3’ for gcc). Hobbit does not attempt to do optimizations of the kind we anticipate from the C compiler, therefore it often makes a serious difference whether the C compiler is run with a strong optimization flag or not.

For the final and fast version of your program you may want to first recompile the whole scm (scmlit for the version scm4e2) using the ‘-DRECKLESS’ flag suppressing error checking: the hobbit-compiled code uses some SCM primitives in the compiled files with the suffix .o, and a number of these primitives become faster when error checking is disabled by ‘-DRECKLESS’. Notice that hobbit never inserts error checking into the code it produces.