I use commercial xHarbour so I don't normally set any parameters, but I will check. If line numbers were not included, would tracelog() still show a trace with line number? Here is an example of what mine looks like.
[c:\projects\diwin11\DIWIN.PRG->MAIN] (91)
Type: C >>>Test Trace Log Entry<<<
OK I checked the compiler log and it does not use -l. Here is one of the compile lines in the log
xhb.exe -o"obj\DIWIN.c" -m -n -pOobj\ -q -gc0 -B -I"C:\fwh\include" -I"C:\xHB\include" -I"C:\xHB\include\w32" "c:\projects\diwin11\DIWIN.PRG"<<<