While attempting to do a distcheck, with gtk-doc turned on (since dist needs the docs for updating the website), there are some warnings about missing cross-references:

gtk-doc: Building HTML
rm -rf ./html
mkdir ./html
cd ./html && gtkdoc-mkhtml cairo ../cairo-docs.xml
test "x" = "x" || ( cd . && cp  html )
gtk-doc: Fixing cross-references
cd . && gtkdoc-fixxref --module-dir=html --html-dir=/usr/local/share/gtk-doc/html 
html/cairo-FreeType-Fonts.html:147: warning: no link for: 'FT-Face' -> (<span class="type">FT_Face</span>).
html/cairo-FreeType-Fonts.html:157: warning: no link for: 'FT-Done-Face' -> (<code class="function">FT_Done_Face()</code>).
html/cairo-FreeType-Fonts.html:198: warning: no link for: 'FT-LOAD-VERTICAL-LAYOUT:CAPS' -> (<code class="literal">FT_LOAD_VERTICAL_LAYOUT</code>).
html/cairo-FreeType-Fonts.html:198: warning: no link for: 'FT-LOAD-FORCE-AUTOHINT:CAPS' -> (<code class="literal">FT_LOAD_FORCE_AUTOHINT</code>).
html/cairo-FreeType-Fonts.html:200: warning: no link for: 'FT-LOAD-TARGET-LIGHT:CAPS' -> (<code class="literal">FT_LOAD_TARGET_LIGHT</code>).
html/cairo-FreeType-Fonts.html:218: warning: no link for: 'FcPattern' -> (<span class="type">FcPattern</span>).
html/cairo-XLib-Surfaces.html:188: warning: no link for: 'Display' -> (<span class="type">Display</span>).
html/cairo-XLib-Surfaces.html:189: warning: no link for: 'Drawable' -> (<span class="type">Drawable</span>).
html/cairo-XLib-Surfaces.html:190: warning: no link for: 'Visual' -> (<span class="type">Visual</span>).
html/cairo-XLib-Surfaces.html:259: warning: no link for: 'Pixmap' -> (<span class="type">Pixmap</span>).
html/cairo-XLib-Surfaces.html:260: warning: no link for: 'Screen' -> (<span class="type">Screen</span>).
html/cairo-cairo-device-t.html:741: warning: no link for: 'cairo-egl-device-create' -> (<code class="function">cairo_egl_device_create()</code>).
html/cairo-Quartz-Surfaces.html:144: warning: no link for: 'CGContextRef' -> (<span class="type">CGContextRef</span>).
html/cairo-Paths.html:464: warning: no link for: 'cairo-stroke-to-path' -> (<code class="function">cairo_stroke_to_path()</code>).
html/cairo-Win32-Fonts.html:139: warning: no link for: 'LOGFONTW:CAPS' -> (<span class="type">LOGFONTW</span>).
html/cairo-Win32-Fonts.html:141: warning: no link for: 'LOGFONT:CAPS' -> (<span class="type">LOGFONT</span>).
html/cairo-Win32-Fonts.html:176: warning: no link for: 'HFONT:CAPS' -> (<span class="type">HFONT</span>).
html/cairo-Win32-Fonts.html:259: warning: no link for: 'HDC:CAPS' -> (<span class="type">HDC</span>).
html/cairo-Quartz-(CGFont)-Fonts.html:92: warning: no link for: 'CGFontRef' -> (<span class="type">CGFontRef</span>).
html/cairo-Quartz-(CGFont)-Fonts.html:124: warning: no link for: 'ATSUFontID' -> (<span class="type">ATSUFontID</span>).
html/cairo-Win32-Surfaces.html:133: warning: no link for: 'cairo-win32-surface-create-with-format' -> (<code class="function">cairo_win32_surface_create_with_format()</code>).
html/cairo-XLib-XRender-Backend.html:96: warning: no link for: 'XRenderPictFormat' -> (<span class="type">XRenderPictFormat</span>).
touch html-build.stamp
mkdir ../../cairo-1.14.3/doc/public/tmpl
mkdir ../../cairo-1.14.3/doc/public/xml
mkdir ../../cairo-1.14.3/doc/public/html
cp ./tmpl/*.sgml ../../cairo-1.14.3/doc/public/tmpl
cp ./xml/*.xml ../../cairo-1.14.3/doc/public/xml
cp ./html/* ../../cairo-1.14.3/doc/public/html
cp ./cairo.types ../../cairo-1.14.3/doc/public/
cp ./cairo-sections.txt ../../cairo-1.14.3/doc/public/
cd ../../cairo-1.14.3/doc/public && rm -f 
gtkdoc-rebase --online --relative --html-dir=../../cairo-1.14.3/doc/public/html
/usr/share/gtk-doc/html/glib/ -> http://library.gnome.org/devel/glib/unstable/ (136)
make[4]: Leaving directory `/home/bryce/src/Cairo/cairo/doc/public'
make[3]: Leaving directory `/home/bryce/src/Cairo/cairo/doc/public'
make[2]: Leaving directory `/home/bryce/src/Cairo/cairo/doc'