diff --git a/TODO b/TODO
index 8cba8a6b..c48174ee 100644
--- a/TODO
+++ b/TODO
@@ -1,11 +1,3 @@
-- test suite is broken, float->int mask I guess
-
-  yes, what about the case where float mask sums to zero, we'll /0 when scaling
-  the output mask
-
-  not sure the fix is right, think again
-
-  maybe look at change in sum? add difference to scale?
 
 - looks like we have a race in tiled threadcache? see 
 
diff --git a/doc/gtk-doc.make b/doc/gtk-doc.make
index e7916563..9ccd0b04 100644
--- a/doc/gtk-doc.make
+++ b/doc/gtk-doc.make
@@ -25,6 +25,7 @@ TARGET_DIR=$(HTML_DIR)/$(DOC_MODULE)
 
 SETUP_FILES = \
 	$(content_files)		\
+	$(expand_content_files)		\
 	$(DOC_MAIN_SGML_FILE)		\
 	$(DOC_MODULE)-sections.txt	\
 	$(DOC_MODULE)-overrides.txt
@@ -86,7 +87,7 @@ GTK_DOC_V_SETUP_0=@echo "  DOC   Preparing build";
 
 setup-build.stamp:
 	-$(GTK_DOC_V_SETUP)if test "$(abs_srcdir)" != "$(abs_builddir)" ; then \
-	    files=`echo $(SETUP_FILES) $(expand_content_files) $(DOC_MODULE).types`; \
+	    files=`echo $(SETUP_FILES) $(DOC_MODULE).types`; \
 	    if test "x$$files" != "x" ; then \
 	        for file in $$files ; do \
 	            destdir=`dirname $(abs_builddir)/$$file`; \
@@ -118,7 +119,7 @@ scan-build.stamp: setup-build.stamp $(HFILE_GLOB) $(CFILE_GLOB)
 	$(GTK_DOC_V_INTROSPECT)if grep -l '^..*$$' $(DOC_MODULE).types > /dev/null 2>&1 ; then \
 	    scanobj_options=""; \
 	    gtkdoc-scangobj 2>&1 --help | grep  >/dev/null "\-\-verbose"; \
-	    if test "$(?)" = "0"; then \
+	    if test "$$?" = "0"; then \
 	        if test "x$(V)" = "x1"; then \
 	            scanobj_options="--verbose"; \
 	        fi; \
@@ -162,17 +163,17 @@ GTK_DOC_V_XREF=$(GTK_DOC_V_XREF_$(V))
 GTK_DOC_V_XREF_=$(GTK_DOC_V_XREF_$(AM_DEFAULT_VERBOSITY))
 GTK_DOC_V_XREF_0=@echo "  DOC   Fixing cross-references";
 
-html-build.stamp: sgml.stamp $(DOC_MAIN_SGML_FILE) $(content_files)
+html-build.stamp: sgml.stamp $(DOC_MAIN_SGML_FILE) $(content_files) $(expand_content_files)
 	$(GTK_DOC_V_HTML)rm -rf html && mkdir html && \
 	mkhtml_options=""; \
 	gtkdoc-mkhtml 2>&1 --help | grep  >/dev/null "\-\-verbose"; \
-	if test "$(?)" = "0"; then \
+	if test "$$?" = "0"; then \
 	  if test "x$(V)" = "x1"; then \
 	    mkhtml_options="$$mkhtml_options --verbose"; \
 	  fi; \
 	fi; \
 	gtkdoc-mkhtml 2>&1 --help | grep  >/dev/null "\-\-path"; \
-	if test "$(?)" = "0"; then \
+	if test "$$?" = "0"; then \
 	  mkhtml_options="$$mkhtml_options --path=\"$(abs_srcdir)\""; \
 	fi; \
 	cd html && gtkdoc-mkhtml $$mkhtml_options $(MKHTML_OPTIONS) $(DOC_MODULE) ../$(DOC_MAIN_SGML_FILE)
@@ -194,11 +195,11 @@ GTK_DOC_V_PDF=$(GTK_DOC_V_PDF_$(V))
 GTK_DOC_V_PDF_=$(GTK_DOC_V_PDF_$(AM_DEFAULT_VERBOSITY))
 GTK_DOC_V_PDF_0=@echo "  DOC   Building PDF";
 
-pdf-build.stamp: sgml.stamp $(DOC_MAIN_SGML_FILE) $(content_files)
+pdf-build.stamp: sgml.stamp $(DOC_MAIN_SGML_FILE) $(content_files) $(expand_content_files)
 	$(GTK_DOC_V_PDF)rm -f $(DOC_MODULE).pdf && \
 	mkpdf_options=""; \
 	gtkdoc-mkpdf 2>&1 --help | grep  >/dev/null "\-\-verbose"; \
-	if test "$(?)" = "0"; then \
+	if test "$$?" = "0"; then \
 	  if test "x$(V)" = "x1"; then \
 	    mkpdf_options="$$mkpdf_options --verbose"; \
 	  fi; \
@@ -223,12 +224,15 @@ clean-local:
 	@if echo $(SCAN_OPTIONS) | grep -q "\-\-rebuild-types" ; then \
 	  rm -f $(DOC_MODULE).types; \
 	fi
+	@if echo $(SCAN_OPTIONS) | grep -q "\-\-rebuild-sections" ; then \
+	  rm -f $(DOC_MODULE)-sections.txt; \
+	fi
 
 distclean-local:
 	@rm -rf xml html $(REPORT_FILES) $(DOC_MODULE).pdf \
 	    $(DOC_MODULE)-decl-list.txt $(DOC_MODULE)-decl.txt
 	@if test "$(abs_srcdir)" != "$(abs_builddir)" ; then \
-	    rm -f $(SETUP_FILES) $(expand_content_files) $(DOC_MODULE).types; \
+	    rm -f $(SETUP_FILES) $(DOC_MODULE).types; \
 	fi
 
 maintainer-clean-local:
diff --git a/libvips/deprecated/im_vips2mask.c b/libvips/deprecated/im_vips2mask.c
index 3bc1f028..d1c56300 100644
--- a/libvips/deprecated/im_vips2mask.c
+++ b/libvips/deprecated/im_vips2mask.c
@@ -145,8 +145,8 @@ im_vips2imask( IMAGE *in, const char *filename )
 
 	double *data;
 	int x, y;
-	double double_ratio;
-	int int_ratio;
+	double double_result;
+	int int_result;
 
 	/* double* only: cast if necessary.
 	 */
@@ -203,11 +203,11 @@ im_vips2imask( IMAGE *in, const char *filename )
 	 * Imaging an input image where every pixel is 1, what will the output
 	 * be?
 	 */
-	double_ratio = 0;
+	double_result = 0;
 	for( y = 0; y < height; y++ )
 		for( x = 0; x < width; x++ )
-			double_ratio += data[x + width * y];
-	double_ratio /= vips_image_get_scale( in );
+			double_result += data[x + width * y];
+	double_result /= vips_image_get_scale( in );
 
 	for( y = 0; y < height; y++ )
 		for( x = 0; x < width; x++ )
@@ -222,26 +222,24 @@ im_vips2imask( IMAGE *in, const char *filename )
 					VIPS_RINT( data[x + y * width] );
 
 	out->scale = VIPS_RINT( vips_image_get_scale( in ) );
+	if( out->scale == 0 )
+		out->scale = 1;
 	out->offset = VIPS_RINT( vips_image_get_offset( in ) );
 
 	/* Now convolve a 1 everywhere image with the int version we've made,
 	 * what do we get?
 	 */
-	int_ratio = 0;
+	int_result = 0;
 	for( y = 0; y < height; y++ )
 		for( x = 0; x < width; x++ )
-			int_ratio += out->coeff[x + width * y];
-	int_ratio /= out->scale;
+			int_result += out->coeff[x + width * y];
+	int_result /= out->scale;
 
-	/* And adjust the scale to get as close to a match as we can. This
-	 * won't work for masks which sum to zero, obviously :-( 
+	/* And adjust the scale to get as close to a match as we can. 
 	 */
-	if( double_ratio != 0.0 ) {
-		out->scale = VIPS_RINT( out->scale * int_ratio / double_ratio );
-		if( out->scale == 0 ) {
-			out->scale = 1;
-		}
-	}
+	out->scale = VIPS_RINT( out->scale + (int_result - double_result) );
+	if( out->scale == 0 ) 
+		out->scale = 1;
 
 	/* We should probably do the same for offset, somehow.
 	 */