When building with AddressSanitizer, gcc warns that `i` may not fit,
because the compiler fails to adequately constrain the possible values
for `i`. Add a control-flow hint to inform gcc about valid values.
Historically, Descent ignored any trailing unconverted characters. The
logic in Descent 1 was tightened in 3368390f37, and then the logic in
Descent 2 was made to mirror Descent 1 in 19699037ce. Restore the lax
parsing logic in both games.
Reported-by: InsanityBringer <https://github.com/dxx-rebirth/dxx-rebirth/issues/464> (issue 5)
Fixes: 3368390f37 ("Check for valid SuperX number") (for Descent 1)
Fixes: 19699037ce ("Move d2x-rebirth/main/bmread.cpp -> similar/main/bmread.cpp") (for Descent 2)
In Descent 2, `type` is initialized at declaration time, then never
rewritten. At the end of the function, `Error` is called if `type` has
not been rewritten. Originally, `type` was hard reset to
`OL_CONTROL_CENTER`, but this reinitialization was removed when
`ObjType` and related data were removed from Descent 2.
Reported-by: InsanityBringer <https://github.com/dxx-rebirth/dxx-rebirth/issues/464> (issue 3)
Fixes: ea7ba7ae87 ("remove ObjType, ObjId, ObjStrength and OL_ constants; use "object" instead of "robot" in some places; draw and place reactors with correct modelnum")
Add macro cf_assert ("control flow" assert) to hint to gcc that certain
conditions are impossible. Use it to avoid generating range checks for
situations that never happen. If the event did happen, the only
consequence would be truncated UI text, rather than a correctness
problem.
