Fix mantis bug 361.

compiler/table_gen.m:
    Fix the bug.

tests/valid/bug361.m:
    The test case.

tests/valid/Mmakefile:
    Enable the test case.

doc/reference_manual.texi:
    Document why, despite not crashing the compiler, the code of the test case,
    and similar code, won't do what it is intended to do.