bug#41979: Reference Manual About New Meta-Vtables

[Sebastian Miele]

doc/ref/api-data.texi from the current master branch contains:

  Additionally, if these checks see that
  the layout of the child vtable contains all the required fields of a
  vtable, in the correct order, then the child vtable will also be a
  meta-table, inheriting a magical bit from the parent.

As far as I understand, the following changes would be correct: Replace
the second occurrence of "vtable" by "meta-vtable". (And maybe replace
"meta-table" by "meta-vtable".)