If a menu was all text except for the last element, the menu would
incorrectly be classifed as all text, and citem would be pinned to the
first element.
Fixes: 14a9657136 ("Use partial_range to store newmenu_item pointer/length")
The index and the value were transposed, and since both were integer
types, the type system was unable to warn that the new code was
incorrect. Swap the variables to bind as intended.
Reported-by: Donkyhotay <https://github.com/dxx-rebirth/dxx-rebirth/issues/544>
Fixes: de4efc4f46 ("Qualify more uses of shared_segment members")
Fix potential buffer overflow if `length` (now `length_of_initial_text`)
is less than the `strlen` computed length of text.
Rename variables to clarify usage.
Eliminate the unnecessary use of `strlen`.
According to a comment from Kreeblah[1], homebrew guarantees a new
enough C++ compiler. Additionally, gcc5 was once new enough, but is now
below the minimum supported version, so installing it is not useful.
Remove the reference to it.
[1]: https://github.com/dxx-rebirth/dxx-rebirth/pull/540#discussion_r486059009
Support for ORTHO_VIEWS has been broken since commit
db514a5ded in December 2004.
`git blame HEAD -L872,+4 -- similar/editor/meddraw.cpp`:
```
db514a5ded main/editor/meddraw.c (Bradley Bell 2004-12-19 13:54:27 +0000 872) }
db514a5ded main/editor/meddraw.c (Bradley Bell 2004-12-19 13:54:27 +0000 873) } else
db514a5ded main/editor/meddraw.c (Bradley Bell 2004-12-19 13:54:27 +0000 874) #if ORTHO_VIEWS
db514a5ded main/editor/meddraw.c (Bradley Bell 2004-12-19 13:54:27 +0000 875) else if ( screen_canvas == TopViewBox->canvas )
```
When ORTHO_VIEWS is true, this code expands to `} else else if (...)`; a
double-else is not legal, so the code cannot have been compiled with
ORTHO_VIEWS enabled. All 4 of the relevant lines date to db514a5ded,
which itself is an import of files from the D1X editor.
