The script side cannot do anything useful with this, because most actions require parameters in global variables, so this is a first grade candidate for rogue mods to make the engine misbehave.
It was only used to avoid traversing the list if all sequences were paused which is an exceptional situation.
On the other hand, the way it counted was not correct so rather than fixing it it seemed more appropriate to remove it entirely.
Select Release configuration explicitly because CMAKE_BUILD_TYPE doesn't work with MSBuild projects
Use long names for command line options of native build tools
Enable minimal verbosity for MSBuild
One sector in an underwater area of KDIZD Z1M3 got tagged with an incorrect Transfer_Heights effect which caused render glitches in that area.
There were also a few AddSectorTag calls without first clearing the sector's tags leading to potentially undefined behavior.
src/p_acs.cpp:3250:75: error: cannot pass object of non-trivial type 'FString' through variadic constructor; call will abort at runtime [-Wnon-pod-varargs]
src/p_conversation.cpp:354:56: error: cannot pass object of non-trivial type 'FString' through variadic constructor; call will abort at runtime [-Wnon-pod-varargs]
src/p_conversation.cpp:438:51: error: cannot pass object of non-trivial type 'FString' through variadic constructor; call will abort at runtime [-Wnon-pod-varargs]
src/p_conversation.cpp:548:58: error: cannot pass object of non-trivial type 'FString' through variadic constructor; call will abort at runtime [-Wnon-pod-varargs]
src/p_conversation.cpp:572:59: error: cannot pass object of non-trivial type 'FString' through variadic constructor; call will abort at runtime [-Wnon-pod-varargs]
src/p_conversation.cpp:584:58: error: cannot pass object of non-trivial type 'FString' through variadic constructor; call will abort at runtime [-Wnon-pod-varargs]
Thanks to the lazy counter it used in its stat display I never noticed that the serializer was incomplete and that UnlinkFromMap did not call its super method.
After changing the counter to be actively counting on each call, all the other issues became immediately apparent.
The interpolator had been changed long ago to use proper GC tracking, so interpolations only can get collected if they had been fully orphaned.
This comment was the main reason why the design flaw in this code never got fixed until recently.
It seems there can be rare conditions where an interpolation is 'lost' and later garbage collected. If that happens after the owning map is gone, all pointers in the interpolation object will be invalid and Destroy would crash while trying to unlink it. So anything that explicitly deletes an interpolation now has to manually unlink it from the map first so that OnDestroy can be kept clean of map references.
Now all this content can be localized. However, since this is actual game content it was placed in a secondary file in zd_extra.pk3, so that it won't affect the GPL-compatible status of the main one.