* avoid undefined behavior from UNREACHABLE on reachable code paths
UNREACHABLE expands to __assume(false) / __builtin_unreachable() in
release builds, which is undefined behavior if the code is ever actually
reached. Many UNREACHABLE sites only guard against unexpected-but-
possible runtime states (values from tables, mission/save files, network
packets, scripting, or user input), so reaching them should degrade
gracefully rather than invoke UB.
Replace UNREACHABLE with Assertion(false, ...) at all such sites. It
still pops an error in debug builds, but in release it is a harmless
no-op that simply falls through to the following code. Sites that are
genuinely unreachable by local invariants (e.g. a switch over a bounded
random number) are left as UNREACHABLE.
A few converted sites had no safe fall-through -- an uninitialized read,
null dereference, or null call would have followed -- so they also get a
minimal recovery: initialize the value, guard the dereference, return
early, or skip the offending item.
Where the converted site was a simple guard of the form
if (x) { Assertion(false, ...); return; }
hoist the check onto the invariant instead:
Assertion(!x, ...);
if (x) { return; }
This states the expectation directly and shows the offending value in
the debug popup, while keeping the same graceful runtime degradation.
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
* addendum
After consultation with Lafiel, use UNREACHABLE in situations that are effectively impossible even if not provably impossible. UNREACHABLE = "this shouldn't ever happen"; Assertion = "if this ever happens, it's a coding error". Also fix a few other sites and change a couple to Warnings.
---------
Co-authored-by: Claude Opus 4.8 (1M context) <[email protected]>
Make these convenient functions even more convenient:
1. Change `object_get_model()` to `object_get_model_num()` and `object_get_model_instance()` to `object_get_model_instance_num()` to more accurately reflect what they do
2. Add new `object_get_model()` and `object_get_model_instance()` functions to return `polymodel*` and `polymodel_instance*` values.
As described in #6445, the `warpIn()` script function did not work correctly for docked ships because the dock leader flag was not set. So, set the flag, but make sure to set it only for the first ship for which `warpIn()` is called. And make sure the flag is removed after the ship finishes arriving.
Also remove an `Int3()` in `shipfx_warpin_start()`. (This Int3() was not actually in the original Volition source code release.)
Fixes#6445.
Properly whacks all ships that are docked together when any are whacked, makes everything more consistent by calling ship_apply_whack instead of physics_apply_whack, whacking in general now unrotates its hit pos to get a world pos like physics whack was expecting and adds a few matrix helper functions.
Switch from 3x specific is_arriving functions to a single with params
Change flag names; replace "ndl" with "dock_follower"
Change dock-arrival helpers to not set follower flag on leaders
There's a number of issues fixed here:
* Radar blips of docked ships were the wrong colour in stage 1
* You could target docked ships in stage 1
* Docked ships thrusters were visible in stage 1
* Hyperspace warptype ship could initially appear at their
warp-destination, then spring back to the correct location to complete
the rest of their warpin (because a docked ship had higher speed than
the dock leader)
There may also be a number of other subtle bugs with docked warpin;
e.g. I suspect (but haven't tested) that AI turrets could fire on
docked ships during warpin
These should also be fixed
Lastly, fixes issue #1867
precalculate warp values before beginning warp, and use them throughout the warp instead of recalculating in every function
standardize on always using the entire docked assembly for length and half-length calculation, instead of some places the assembly and some places just the dock leader
consolidate and simplify the compute_warpout* functions in light of the above
This can be used for mark parts of the code which should be unreachable
in normal execution. In debug mode, if such a statement is reached an
Error dialog is shown which aborts the execution. In release mode the
macro is replaced with a compiler specific expression that lets the
compiler know that this part is unreachable which allows it to optimize
the code better.
* Adds a warning for debug users when an unknown ship_state is passed to red_alert_delete.
* Removes commented-out code
* Doxy's ship_cleanup()
*Conform to each file's style.
*Extend ship_cleanup to better handle red-alert deletion.
*Also treat cleanup_mode as a flagset, instead of an enum as it was previously.
*Use existing methods to determine dock status and find the head of the dock list.
*Fixes a derp with dock_dead_undock_all()
*Doccument some docking methods in object.h
*Address requested changes.
This introduces a new mechanism for handling bit flags. Instead of using an int (or two, or three) to write bits into, this uses the std::bitset in a wrapper class that accepts an enum class as input. This means that certain classes of errors we've had a few of in the engine, where a coder used the wrong set of flags or checked them against the wrong variable (SF_STEALTH vs SIF_STEALTH, for example) can now be detected at a compiler level rather than not at all.
