diff --git a/libvips/resample/interpolate.c b/libvips/resample/interpolate.c
index 2a3b4431..1aaf9e63 100644
--- a/libvips/resample/interpolate.c
+++ b/libvips/resample/interpolate.c
@@ -69,29 +69,6 @@
  * A number of image interpolators.
  */
 
-/*
- * FAST_PSEUDO_FLOOR is a floor and floorf replacement which has been
- * found to be faster on several linux boxes than the library
- * version. It returns the floor of its argument unless the argument
- * is a negative integer, in which case it returns one less than the
- * floor. For example:
- *
- * FAST_PSEUDO_FLOOR(0.5) = 0
- *
- * FAST_PSEUDO_FLOOR(0.) = 0
- *
- * FAST_PSEUDO_FLOOR(-.5) = -1
- *
- * as expected, but
- *
- * FAST_PSEUDO_FLOOR(-1.) = -2
- *
- * The locations of the discontinuities of FAST_PSEUDO_FLOOR are the
- * same as floor and floorf; it is just that at negative integers the
- * function is discontinuous on the right instead of the left.
- */
-#define FAST_PSEUDO_FLOOR(x) ( (int)(x) - ( (x) < 0. ) )
-
 G_DEFINE_ABSTRACT_TYPE( VipsInterpolate, vips_interpolate, VIPS_TYPE_OBJECT );
 
 #ifdef DEBUG