use bb_xbind/bb_xlisten
[oweals/busybox.git] / coreutils / sort.c
index 60fc9522255f13882fa1789310b4e0fbddea760a..fb58f62790124a596aff0ff18cfad91c2321d868 100644 (file)
@@ -176,12 +176,14 @@ static int compare_keys(const void *xarg, const void *yarg)
                                /* not numbers < NaN < -infinity < numbers < +infinity) */
                                if(x==xx) retval=(y==yy ? 0 : -1);
                                else if(y==yy) retval=1;
-                               else if(isnan(dx)) retval=isnan(dy) ? 0 : -1;
-                               else if(isnan(dy)) retval=1;
-                               else if(isinf(dx)) {
-                                       if(dx<0) retval=((isinf(dy) && dy<0) ? 0 : -1);
-                                       else retval=((isinf(dy) && dy>0) ? 0 : 1);
-                               } else if(isinf(dy)) retval=dy<0 ? 1 : -1;
+                               /* Check for isnan */
+                               else if(dx != dx) retval = (dy != dy) ? 0 : -1;
+                               else if(dy != dy) retval = 1;
+                               /* Check for infinity.  Could underflow, but it avoids libm. */
+                               else if(1.0/dx == 0.0) {
+                                       if(dx<0) retval=((1.0/dy == 0.0 && dy<0) ? 0 : -1);
+                                       else retval=((1.0/dy == 0.0 && dy>0) ? 0 : 1);
+                               } else if(1.0/dy == 0.0) retval=dy<0 ? 1 : -1;
                                else retval=dx>dy ? 1 : (dx<dy ? -1 : 0);
                                break;
                        }