On a sun4u machine compile with gcc version 4

sunw389:fastlz>gcc 6pack.c fastlz.c -o 6pack -g
sunw389:fastlz>gdb 6pack
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(gdb) run 6pack 6pack.6p

Program received signal SIGSEGV, Segmentation fault.
0x000120d0 in fastlz2_compress (input=0xffbdec10, length=34332,
output=0xffb9ec10) at fastlz.c:199
199         HASH_FUNCTION(hval,ip);
(gdb)


Using Sun studio 11 cc without -fast option works.