I was adding some functions to the gtk_docs_override.xml and the parser
wouldn't parse this correctly:
<function name="gtk_adjustment_clamp_page">
<description>
Updates the Adjustment value to ensure that the range between the
parameters @lower and @upper is in the current page (i.e. between @value
and @value + @page_size).  If this range is larger than the page size, then
only the start of it will be in the current page.  A "changed" signal will
be emitted if the value is changed.
</description>
<parameters>
<parameter name="upper">
<parameter_description> The upper value.
</parameter_description>
</parameter>
<parameter name="lower">
<parameter_description> The lower value.
</parameter_description>
</parameter>
</parameters>
<return>
</return>
</function>

What it gave me was this:

   /** Updates the Adjustment value to ensure that the range between the
parameters @a lower  and @a upper  is in the current page (i.e.\ between @a
value  and @a value  + @a page_size ).  If this range is larger than the
page size, then only the start of it will be in the current page.  A
"changed" signal will be emitted if the value is changed.
   * @param lower The lower value.
   */
  void clamp_page(double lower, double upper);

It should have one more @param after the @param lower, according to the xml