diff --git a/scripts/uni-build-dependencies.sh b/scripts/uni-build-dependencies.sh
index dc61f743..784a1915 100755
--- a/scripts/uni-build-dependencies.sh
+++ b/scripts/uni-build-dependencies.sh
@@ -513,7 +513,7 @@ if [ $1 ]; then
     exit $?
   fi
   if [ $1 = "cgal" ]; then
-    build_cgal 4.0.2 use-sys-libs
+    build_cgal 4.1 use-sys-libs
     exit $?
   fi
   if [ $1 = "opencsg" ]; then
diff --git a/src/boost-utils.cc b/src/boost-utils.cc
index 51270474..534cbaad 100644
--- a/src/boost-utils.cc
+++ b/src/boost-utils.cc
@@ -1,3 +1,4 @@
+#include "boosty.h"
 #include "boost-utils.h"
 #include <stdio.h>
 #include <iostream>
@@ -7,8 +8,8 @@
 fs::path boostfs_relative_path(const fs::path &path, const fs::path &relative_to)
 {
 	// create absolute paths
-	fs::path p = fs::absolute(boostfs_normalize(path));
-	fs::path r = fs::absolute(relative_to);
+	fs::path p = boosty::absolute(boostfs_normalize(path));
+	fs::path r = boosty::absolute(relative_to);
 	
 	// if root paths are different, return absolute path
 	if (p.root_path() != r.root_path())
@@ -46,16 +47,17 @@ fs::path boostfs_relative_path(const fs::path &path, const fs::path &relative_to
 // Will normalize the given path, i.e. remove any redundant ".." path elements.
 fs::path boostfs_normalize(const fs::path &path)
 {
-	fs::path absPath = absolute(path);
+	fs::path absPath = boosty::absolute(path);
 	fs::path::iterator it = absPath.begin();
-	fs::path result = *it++;
+	fs::path result = *it;
+	if (it!=absPath.end()) it++;
 
 	// Get canonical version of the existing part
 	for(;exists(result) && it != absPath.end(); ++it) {
 		result /= *it;
 	}
-	result = canonical(result.parent_path());
-	--it;
+	result = boosty::canonical(result.parent_path());
+	if (it!=absPath.begin()) it--;
 
 	// For the rest remove ".." and "." in a path with no symlinks
 	for (; it != absPath.end(); ++it) {
@@ -98,8 +100,8 @@ boostfs_uncomplete(fs::path const p, fs::path const base)
 		which it most likely is... but then base shouldn't be a filename so... */
 
 	// create absolute paths
-	fs::path abs_p = fs::absolute(boostfs_normalize(p));
-	fs::path abs_base = fs::absolute(base);
+	fs::path abs_p = boosty::absolute(boostfs_normalize(p));
+	fs::path abs_base = boosty::absolute(base);
 
 	fs::path from_path, from_base, output;
 
diff --git a/src/boosty.h b/src/boosty.h
index 6ec417a6..5c820026 100644
--- a/src/boosty.h
+++ b/src/boosty.h
@@ -10,9 +10,8 @@
  versions of boost found on popular versions of linux, circa early 2012.
 
  design
-  hope that the user is compiling with boost>1.46 + filesystem v3
-  if not, fall back to older deprecated functions, and rely on
-  testing to find bugs. implement the minimum needed by OpenSCAD and no more.
+  the boost filsystem changed around 1.46-1.48. we do a large #ifdef
+  based on boost version that wraps various functions appropriately.
   in a few years, this file should be deleted as unnecessary.
 
  see also
@@ -28,6 +27,7 @@
 #include <boost/version.hpp>
 #include <boost/filesystem.hpp>
 namespace fs = boost::filesystem;
+#include "printutils.h"
 
 namespace boosty {
 
@@ -77,6 +77,62 @@ inline std::string extension_str( fs::path p)
 
 #endif
 
+
+
+
+
+#if BOOST_VERSION >= 104800
+
+inline fs::path canonical( fs::path p, fs::path p2 )
+{
+	return fs::canonical( p, p2, NULL );
+}
+
+inline fs::path canonical( fs::path p )
+{
+	return fs::canonical( p, fs::current_path(), NULL );
+}
+
+#else
+
+inline fs::path canonical( fs::path p, fs::path p2 )
+{
+	// dotpath: win32/mac builds will be using newer versions of boost
+	// so we can treat this as though it is unix only
+	const fs::path dot_path(".");
+	const fs::path dot_dot_path("..");
+	fs::path result;
+	if (p=="")
+	{
+		p=p2;
+	}
+	for (fs::path::iterator itr = p.begin(); itr != p.end(); itr++)
+	{
+		if (*itr == dot_path) continue;
+		if (*itr == dot_dot_path)
+		{
+			result.remove_filename();
+			continue;
+		}
+		result /= *itr;
+		if (fs::is_symlink(result))
+		{
+			PRINT("WARNING: canonical() wrapper can't do symlinks. upgrade boost to >1.48");
+		}
+	}
+	return result;
+}
+
+inline fs::path canonical( fs::path p )
+{
+	return canonical( p, fs::current_path() );
+}
+
+#endif
+
+
+
+
 } // namespace
 
 #endif
diff --git a/src/value.cc b/src/value.cc
index ae810a23..ebb825d4 100644
--- a/src/value.cc
+++ b/src/value.cc
@@ -39,7 +39,9 @@
 
 std::ostream &operator<<(std::ostream &stream, const Filename &filename)
 {
-  stream << QuotedString(boosty::stringy(boostfs_uncomplete(filename, fs::current_path())));
+  fs::path fnpath = fs::path( (std::string)filename );
+  fs::path fpath = boostfs_uncomplete(fnpath, fs::current_path());
+  stream << QuotedString(boosty::stringy( fpath ));
   return stream;
 }