Function xsltSetGenericDebugFunc 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn xsltSetGenericDebugFunc(
    ctx: *mut c_void,
    handler: Option<unsafe extern "C" fn(*mut c_void, *const c_char)>,
)

Set the generic debug handler (upstream xsltSetGenericDebugFunc).

UPSTREAM-PARITY

void xsltSetGenericDebugFunc(void *ctx, xmlGenericErrorFunc handler);

With a NULL handler, messages go to stderr; with a NULL context they are suppressed (upstream’s default debug handler checks the context).