cast void* to double*

src/stream_grb.c

@@ -620,7 +620,7 @@ int grb_write_var_slice(stream_t *streamptr, int varID, int levelID, int memtype
     }
 
   nbytes = grbEncode(filetype, varID, levelID, vlistID, gridID, zaxisID, date, time, tsteptype, numavg, 
-		     datasize, data, nmiss, &gribbuffer, ljpeg, gc);
+		     datasize, (const double*) data, nmiss, &gribbuffer, ljpeg, gc);
 
   if ( streamptr->comptype == COMPRESS_SZIP )
     nbytes = grbSzip(filetype, gribbuffer, nbytes);