nixpkgs/pkgs/development/compilers/vala/disable-graphviz-0.40.12.patch

diff --git i/configure.ac w/configure.ac
index 694ffd200..915062053 100644
--- i/configure.ac
+++ w/configure.ac
@@ -112,34 +112,38 @@ PKG_CHECK_MODULES(GMODULE, gmodule-2.0 >= $GLIB_REQUIRED)
 AC_SUBST(GMODULE_CFLAGS)
 AC_SUBST(GMODULE_LIBS)
 
-PKG_CHECK_MODULES(LIBGVC, libgvc >= $LIBGVC_REQUIRED)
-AC_MSG_CHECKING([for CGRAPH])
-cgraph_tmp_LIBADD="$LIBADD"
-cgraph_tmp_CFLAGS="$CFLAGS"
-LIBADD="$LIBADD $LIBGVC_LIBS"
-CFLAGS="$CFLAGS $LIBGVC_CFLAGS"
-AC_RUN_IFELSE(
-	[AC_LANG_SOURCE([
-		#include <gvc.h>
-
-		int main(void) {
-			#ifdef WITH_CGRAPH
-				return 0;
-			#else
-				return -1;
-			#endif
-		}
-	])], [
-		AC_MSG_RESULT([yes])
-		VALAFLAGS="$VALAFLAGS -D WITH_CGRAPH"
-		have_cgraph=yes
-	], [
-		AC_MSG_RESULT([no])
-		have_cgraph=no
-	]
-)
-LIBADD="$cgraph_tmp_LIBADD"
-CFLAGS="$cgraph_tmp_CFLAGS"
+AC_ARG_ENABLE(graphviz, AS_HELP_STRING([--disable-graphviz], [Disable graphviz usage for valadoc]), enable_graphviz=$enableval, enable_graphviz=yes)
+if test x$enable_graphviz = xyes; then
+	PKG_CHECK_MODULES(LIBGVC, libgvc >= $LIBGVC_REQUIRED)
+	AC_MSG_CHECKING([for CGRAPH])
+	VALAFLAGS="$VALAFLAGS -D HAVE_GRAPHVIZ"
+	cgraph_tmp_LIBADD="$LIBADD"
+	cgraph_tmp_CFLAGS="$CFLAGS"
+	LIBADD="$LIBADD $LIBGVC_LIBS"
+	CFLAGS="$CFLAGS $LIBGVC_CFLAGS"
+	AC_RUN_IFELSE(
+		[AC_LANG_SOURCE([
+			#include <gvc.h>
+			int main(void) {
+				#ifdef WITH_CGRAPH
+					return 0;
+				#else
+					return -1;
+				#endif
+			}
+		])], [
+			AC_MSG_RESULT([yes])
+			VALAFLAGS="$VALAFLAGS -D WITH_CGRAPH"
+			have_cgraph=yes
+		], [
+			AC_MSG_RESULT([no])
+			have_cgraph=no
+		]
+	)
+	LIBADD="$cgraph_tmp_LIBADD"
+	CFLAGS="$cgraph_tmp_CFLAGS"
+fi
+AM_CONDITIONAL(ENABLE_GRAPHVIZ, test x$enable_graphviz = xyes)
 AM_CONDITIONAL(HAVE_CGRAPH, test "$have_cgraph" = "yes")
 
 AC_PATH_PROG([XSLTPROC], [xsltproc], :)
diff --git i/libvaladoc/Makefile.am w/libvaladoc/Makefile.am
index f3f790e76..3c5dc4c80 100644
--- i/libvaladoc/Makefile.am
+++ w/libvaladoc/Makefile.am
@@ -128,10 +128,6 @@ libvaladoc_la_VALASOURCES = \
 	content/tablerow.vala \
 	content/taglet.vala \
 	content/text.vala \
-	charts/chart.vala \
-	charts/chartfactory.vala \
-	charts/hierarchychart.vala \
-	charts/simplechartfactory.vala \
 	parser/manyrule.vala \
 	parser/oneofrule.vala \
 	parser/optionalrule.vala \
@@ -158,13 +154,24 @@ libvaladoc_la_VALASOURCES = \
 	highlighter/codetoken.vala \
 	highlighter/highlighter.vala \
 	html/basicdoclet.vala \
-	html/htmlchartfactory.vala \
 	html/linkhelper.vala \
 	html/cssclassresolver.vala \
 	html/htmlmarkupwriter.vala \
 	html/htmlrenderer.vala \
 	$(NULL)
 
+if ENABLE_GRAPHVIZ
+libvaladoc_la_VALASOURCES += \
+	charts/chart.vala \
+	charts/chartfactory.vala \
+	charts/hierarchychart.vala \
+	charts/simplechartfactory.vala \
+	html/htmlchartfactory.vala \
+	$(NULL)
+
+LIBGVC_PKG = --vapidir $(top_srcdir)/vapi --pkg libgvc
+endif
+
 libvaladoc@PACKAGE_SUFFIX@_la_SOURCES = \
 	libvaladoc.vala.stamp \
 	$(libvaladoc_la_VALASOURCES:.vala=.c) \
@@ -184,11 +191,11 @@ libvaladoc.vala.stamp: $(libvaladoc_la_VALASOURCES)
 		--library valadoc \
 		--vapi valadoc@PACKAGE_SUFFIX@.vapi \
 		--vapidir $(top_srcdir)/vapi --pkg gmodule-2.0 \
-		--vapidir $(top_srcdir)/vapi --pkg libgvc \
 		--vapidir $(top_srcdir)/gee --pkg gee \
 		--vapidir $(top_srcdir)/vala --pkg vala \
 		--vapidir $(top_srcdir)/ccode --pkg ccode \
 		--vapidir $(top_srcdir)/codegen --pkg codegen \
+		$(LIBGVC_PKG) \
 		--pkg config \
 		$(filter %.vala %.c,$^)
 	touch $@
@@ -217,6 +224,9 @@ nodist_pkgconfig_DATA = valadoc@PACKAGE_SUFFIX@.pc
 
 valadoc@PACKAGE_SUFFIX@.pc: valadoc.pc
 	cp $< $@
+if !ENABLE_GRAPHVIZ
+	sed -i "s/libgvc //g" $@
+endif
 
 vapidir = $(datadir)/vala/vapi
 dist_vapi_DATA = valadoc@PACKAGE_SUFFIX@.vapi
@@ -224,6 +234,9 @@ nodist_vapi_DATA = valadoc@PACKAGE_SUFFIX@.deps
 
 valadoc@PACKAGE_SUFFIX@.deps: valadoc.deps
 	cp $< $@
+if !ENABLE_GRAPHVIZ
+	sed -i "s/libgvc//g" $@
+endif
 
 EXTRA_DIST = \
 	$(libvaladoc_la_VALASOURCES) \
diff --git i/libvaladoc/html/basicdoclet.vala w/libvaladoc/html/basicdoclet.vala
index 192e488cd..ec0960222 100644
--- i/libvaladoc/html/basicdoclet.vala
+++ w/libvaladoc/html/basicdoclet.vala
@@ -46,7 +46,11 @@ public abstract class Valadoc.Html.BasicDoclet : Api.Visitor, Doclet {
 	protected HtmlRenderer _renderer;
 	protected Html.MarkupWriter writer;
 	protected Html.CssClassResolver cssresolver;
+#if HAVE_GRAPHVIZ
 	protected Charts.Factory image_factory;
+#else
+	protected void* image_factory;
+#endif
 	protected ErrorReporter reporter;
 	protected string package_list_link = "../index.html";
 
@@ -120,7 +124,9 @@ public abstract class Valadoc.Html.BasicDoclet : Api.Visitor, Doclet {
 		this.linker = new LinkHelper ();
 
 		_renderer = new HtmlRenderer (settings, this.linker, this.cssresolver);
+#if HAVE_GRAPHVIZ
 		this.image_factory = new SimpleChartFactory (settings, linker);
+#endif
 	}
 
 
@@ -1026,6 +1032,7 @@ public abstract class Valadoc.Html.BasicDoclet : Api.Visitor, Doclet {
 	}
 
 	protected void write_image_block (Api.Node element) {
+#if HAVE_GRAPHVIZ
 		if (element is Class || element is Interface || element is Struct) {
 			unowned string format = (settings.use_svg_images ? "svg" : "png");
 			var chart = new Charts.Hierarchy (image_factory, element);
@@ -1045,6 +1052,7 @@ public abstract class Valadoc.Html.BasicDoclet : Api.Visitor, Doclet {
 									   this.get_img_path_html (element, format)});
 			writer.add_usemap (chart);
 		}
+#endif
 	}
 
 	public void write_namespace_content (Namespace node, Api.Node? parent) {
diff --git i/libvaladoc/html/htmlmarkupwriter.vala w/libvaladoc/html/htmlmarkupwriter.vala
index dcc4dad76..cf9c860b8 100644
--- i/libvaladoc/html/htmlmarkupwriter.vala
+++ w/libvaladoc/html/htmlmarkupwriter.vala
@@ -51,12 +51,16 @@ public class Valadoc.Html.MarkupWriter : Valadoc.MarkupWriter {
 		}
 	}
 
+#if HAVE_GRAPHVIZ
 	public MarkupWriter add_usemap (Charts.Chart chart) {
 		string? buf = (string?) chart.write_buffer ("cmapx");
 		if (buf != null) {
 			raw_text ("\n");
 			raw_text ((!) buf);
 		}
+#else
+	public MarkupWriter add_usemap (void* chart) {
+#endif
 
 		return this;
 	}