When all else fails, you may wish to generate a bytecode by bytecode log of every virtual instruction the Muq bytecode engine executes. (Save a forest: don't run the output to hard copy!)
To do this, look in `c/jobbuild.c' for
#if JOB_PASS_IN_PARAMETERS
fputs("#define JOB_NEXT \\\n", fd );
/* Uncomment next for a debug trace (see also job_run()): */
/* fputs("job_Print1(stdout,jSpc,jSs);\\\n", fd );*/
fputs("{++jSops; \\\n", fd );
fputs(" ((Job_Fast_Prim*)jStabl)[ \\\n", fd );
fputs(" *jSpc | \\\n", fd );
fputs(" (job_Type1[jSs[-1]&0xFF]) | \\\n", fd );
fputs(" job_Type0[jSs[ 0]&0xFF] | \\\n", fd );
fputs(" (jSops & JOB_OPS_COUNT_MASK) \\\n", fd );
fputs(" ](JOB_PRIM_ARGS);}\n", fd );
#else
fputs("#define JOB_NEXT \\\n", fd );
/* Uncomment next for a debug trace (see also job_run()): */
/* fputs("job_Print1(stdout,jSpc,jSs);\\\n", fd ); */
fputs(" ((Job_Fast_Prim*)jStabl)[ \\\n", fd );
fputs(" *jSpc | \\\n", fd );
fputs(" (job_Type1[jSs[-1]&0xFF]) | \\\n", fd );
fputs(" job_Type0[jSs[ 0]&0xFF] | \\\n", fd );
fputs(" (++jSops & JOB_OPS_COUNT_MASK) \\\n", fd );
fputs(" ](JOB_PRIM_ARGS)\n", fd );
#endif
and uncomment both of the indicated lines. Then go into `job.t'
and find in function job_run() the section reading
/* Uncomment next line for a handy trace when debugging: */
/* job_Print1(stdout,jS.pc,jS.s); */
/* See also JOB_NEXT in jobbuild.c */
and uncomment. Recompile ... and stand back.
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