typedef struct libxml_xpathCallback { void *ns_uri; } libxml_xpathCallback; typedef libxml_xpathCallback libxml_xpathCallbackArray[]; libxml_xpathCallbackArray *libxml_xpathCallbacks; void foo1(void); void foo (void) { if ((*libxml_xpathCallbacks)[3].ns_uri != ((void *)0)) foo1(); }