------- Comment #10 from niklaus at gmail dot com 2008-09-06 21:23 ------- (In reply to comment #8) > (In reply to comment #7) > > Does increasing bits cause floating point errors. How could 64 bit precison > > give correct result where as 80 bit give incorrect one. > > You can have rounding errors whether you increase the precision or not. In > particular, in practice, function pow() is not correctly rounded, and worse, > the error may be quite high. So, I'd say that whatever the choice made by > Linux, your code may be regarded as wrong (and I think this bug is just > invalid, as you could have similar problems with SSE2).
The funny thing is that this only happens with -O2 or -O1 but not with -O0 ie no optimization it is all correct , when we optimize the results start varying. > > > [EMAIL PROTECTED]:~/prog/tju$ gcc -O2 -mfpmath=sse bug_short.c -lm > > bug_short.c:1: warning: SSE instruction set disabled, using 387 arithmetics > > You probably need another compilation flag, like -march=pentium4. > -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37390 ------- You are receiving this mail because: ------- You are on the CC list for the bug, or are watching someone who is. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
