search for: 250kx1k

...lly any calls that use long double will be affected: qadd: 4.5s (gcc3 opt), 6.7s (Agcc4 opt), 7.4s (gcc3), 7.9s (gcc4 opt +dyngcc), 10.5s (Agcc4), 10.6s (gcc4 dyngcc) (this test basically runs 500x 1M long double additions on an array - it's even more extreme if you run it on short arrays : 250kx1k will give 2s on gcc3 and 7.7s on gcc4) Now, the actual reason is that gcc3 simply ignores "long double" and performs all computation using regular double precision (sizeof(long double)=8 in gcc3 and 16 in gcc4). What this means is that you lose precision in gcc3. To illustrate th...