diff --git a/src/cache/ftcbasic.c b/src/cache/ftcbasic.c
index 1760c5f..7310383 100644
--- a/src/cache/ftcbasic.c
+++ b/src/cache/ftcbasic.c
@@ -26,6 +26,7 @@
 #include "ftccback.h"
 #include "ftcerror.h"
 
+#undef  FT_COMPONENT
 #define FT_COMPONENT  cache
 
 
diff --git a/src/smooth/ftgrays.c b/src/smooth/ftgrays.c
index d982c28..5d5d016 100644
--- a/src/smooth/ftgrays.c
+++ b/src/smooth/ftgrays.c
@@ -333,7 +333,9 @@
 #define PIXEL_BITS  8
 
 #define ONE_PIXEL       ( 1 << PIXEL_BITS )
+#undef TRUNC
 #define TRUNC( x )      (TCoord)( (x) >> PIXEL_BITS )
+#undef FRACT
 #define FRACT( x )      (TCoord)( (x) & ( ONE_PIXEL - 1 ) )
 
 #if PIXEL_BITS >= 6