The following, fairly common, C idiom

  typedef guint32 PangoGlyph;

  #define PANGO_GLYPH_EMPTY  ((PangoGlyph)0xfffffffff)

Produces this in the .gir:
 
    <constant name="GLYPH_EMPTY" value="268435455" c:type="PANGO_GLYPH_EMPTY">
      <type c:type="PangoGlyph"/>
    </constant>

Which then fails in gir-compile with 
  Pango-1.0.gir:40:34: error: Line 40, character 34: The attribute 'name' on
     the  element 'type' must be specified
  error parsing file Pango-1.0.gir: Line 40, character 34: The attribute 'name'
     on the element 'type' must be specified

I attempted to coerce the type back to guint32 with a (type) annotation on PANGO_GLYPH_EMPTY, but it was ignored.

One can work around the problem by converting the define to an enum:

enum
  {
     PANGO_GLYPH_EMPTY = ((PangoGlyph)0xffffffff)
  };

but ISTM g-i should handle the define case as well.