libxrdeveloper's documentation
#define xr_trace (   mask,
  fmt,
  args... 
)    do { if (G_UNLIKELY(xr_debug_enabled & mask)) _xr_debug(G_STRFUNC, fmt, ## args); } while(0)

Conditional trace message.

Parameters
maskXR_DEBUG_* constant that enables this message.
fmtMessage format (printf like).
argsVariable arguments.
Documentation for libxr, Wed Apr 27 2016 22:07:49.