[DynInst_API:] [dyninst/dyninst] 9e8552: Make a default module a class invariant in Symtab ...

[Tim Haines <noreply@xxxxxxxxxx>]

  Branch: refs/heads/master
  Home:   https://github.com/dyninst/dyninst
  Commit: 9e8552508050891732c5aeb82e0fe456614f08bb
      https://github.com/dyninst/dyninst/commit/9e8552508050891732c5aeb82e0fe456614f08bb
  Author: Tim Haines <thaines.astro@xxxxxxxxx>
  Date:   2023-09-28 (Thu, 28 Sep 2023)

  Changed paths:
    M symtabAPI/src/Symtab-lookup.C
    M symtabAPI/src/Symtab.C
    M symtabAPI/src/symtab_impl.hpp

  Log Message:
  -----------
  Make a default module a class invariant in Symtab (#1538)

This simplifies the handling of modules and ensures a default
always exists. Creation must happen after the MappedFile has
been created (Symtab::file() checks that one has been created),
but before the symbols are assigned to a Module.