diff --git a/libvips/create/perlin.c b/libvips/create/perlin.c
index a6651f90..b0efdcc8 100644
--- a/libvips/create/perlin.c
+++ b/libvips/create/perlin.c
@@ -267,7 +267,7 @@ vips_perlin_make_tables( void *client )
 	int i;
 
 	for( i = 0; i < 256; i++ ) {
-		double angle = 2 * M_PI * i / 256.0;
+		double angle = 2 * VIPS_PI * i / 256.0;
 
 		vips_perlin_cos[i] = cos( angle );
 		vips_perlin_sin[i] = sin( angle );
diff --git a/libvips/foreign/rawsave.c b/libvips/foreign/rawsave.c
index 63f4ded2..7b4bfafa 100644
--- a/libvips/foreign/rawsave.c
+++ b/libvips/foreign/rawsave.c
@@ -57,7 +57,9 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#ifdef HAVE_UNISTD_H
 #include <unistd.h>
+#endif
 #include <string.h>
 
 #include <vips/vips.h>
diff --git a/libvips/include/vips/util.h b/libvips/include/vips/util.h
index f481e943..0d456c71 100644
--- a/libvips/include/vips/util.h
+++ b/libvips/include/vips/util.h
@@ -79,7 +79,7 @@ extern "C" {
 #define VIPS_ISINF( V ) isinf( V )
 #define VIPS_FLOOR( V ) floor( V )
 #define VIPS_CEIL( V ) ceil( V )
-#define VIPS_RINT( R ) rint( V )
+#define VIPS_RINT( V ) rint( V )
 #define VIPS_ROUND( V ) round( V )
 #define VIPS_FABS( V ) VIPS_ABS( V )
 #define VIPS_FMAX( A, B ) VIPS_MAX( A, B )
diff --git a/libvips/iofuncs/mapfile.c b/libvips/iofuncs/mapfile.c
index 37e1cf90..33911aac 100644
--- a/libvips/iofuncs/mapfile.c
+++ b/libvips/iofuncs/mapfile.c
@@ -87,6 +87,7 @@
 
 #ifdef OS_WIN32
 #include <windows.h>
+#include <io.h>
 #endif /*OS_WIN32*/
 
 void *
diff --git a/libvips/iofuncs/memory.c b/libvips/iofuncs/memory.c
index 3bb7352e..d877e2e0 100644
--- a/libvips/iofuncs/memory.c
+++ b/libvips/iofuncs/memory.c
@@ -59,7 +59,12 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
+#ifdef HAVE_UNISTD_H
 #include <unistd.h>
+#endif
+#ifdef HAVE_IO_H
+#include <io.h>
+#endif /*HAVE_IO_H*/
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
diff --git a/libvips/iofuncs/util.c b/libvips/iofuncs/util.c
index c7026333..a9f3bb86 100644
--- a/libvips/iofuncs/util.c
+++ b/libvips/iofuncs/util.c
@@ -48,6 +48,9 @@
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif /*HAVE_UNISTD_H*/
+#ifdef HAVE_IO_H
+#include <io.h>
+#endif /*HAVE_IO_H*/
 #include <fcntl.h>
 
 #ifdef OS_WIN32
diff --git a/libvips/mosaicing/im_lrmerge.c b/libvips/mosaicing/im_lrmerge.c
index 5ad06b0e..6512e2ae 100644
--- a/libvips/mosaicing/im_lrmerge.c
+++ b/libvips/mosaicing/im_lrmerge.c
@@ -165,7 +165,7 @@ im__make_blend_luts( void )
 		return( -1 ); 
 
 	for( x = 0; x < BLEND_SIZE; x++ ) {
-		double a = IM_PI * x / (BLEND_SIZE - 1.0);
+		double a = VIPS_PI * x / (BLEND_SIZE - 1.0);
 
 		im__coef1[x] = (cos( a ) + 1.0) / 2.0;
 		im__coef2[x] = 1.0 - im__coef1[x];