Doxygen doesn't warn for missing parameter if none is already documented

Question

If I write this (in the class CPosition, file position.h):

/**
 * @brief Constructor
 * @param x x coordinate
 */
CPosition(int x, int y);

Doxygen warns me:

error: The following parameters of CPosition::CPosition(int x, int y) are not documented:
parameter 'y'

But if no parameter is documented in the CPosition constructor, like this:

/**
 * @brief Constructor
 */
CPosition(int x, int y);

Doxygen doesn't warn me at all.

What configuration am I missing if I want doxygen to warn even if no parameter is already documented ?

---

Some relevant configuration directives of my Doxyfile:

WARN_IF_UNDOCUMENTED   = YES
WARN_IF_DOC_ERROR      = YES
WARN_NO_PARAMDOC       = YES