Patch submitted upstream in
http://lists.cairographics.org/archives/cairo/2015-May/026303.html

diff -u -r ../cairo-1.14.2/src/cairo-misc.c ./src/cairo-misc.c
--- ../cairo-1.14.2/src/cairo-misc.c	2015-03-10 18:21:07.000000000 -0400
+++ ./src/cairo-misc.c	2015-05-31 13:43:50.883573386 -0400
@@ -774,7 +774,7 @@
 const char *
 cairo_get_locale_decimal_point (void)
 {
-    return '.';
+    return ".";
 }
 #endif