Change from heap::increase to heap::decrease in include/util/query_heap.hpp with possible segfault in rare circumstances

[mugr1x]

Issue

I think the DecreaseKey in include/util/query_heap.hpp wrongly calls the increase instead of decrease function from boost::heap.

Steps to reproduce

See the docs:
https://www.boost.org/doc/libs/1_76_0/doc/html/boost/heap/d_ary_heap.html#id-1_3_18_6_2_1_1_1_22_17-bb
My thoughts behind this are that there is logic in multiple files e.g. include/engine/routing_algorithms/routing_base_mld.hpp that checks for a certain "to_weight" to be smaller than the current "toHeapNode->weight" and then calls DecreaseKey which in turn calls heap.increase with "to_weight".
So the docs say: "The new value is expected to be less than the current one" for decrease not increase which is the other way round. Wouldn't it be better to replace increase with decrease then to fit the docs ?
Also I guess it kinda fixed a segfault for me while testing. (I know for sure it was this one, however might only have emerged with now reverted changes since now not using std::optional instead just pointers)
Am I completely mistaken here ? I still get from A to B though using my setup e.g. with the Germany map.

[SiarheiFedartsou]

Hey

Also I guess it kinda fixed a segfault for me while testing.

Can you reproduce it? If so, could you please share how I would do that?

[mugr1x]

Hello, as for the segfault it occured when I tried switching to std::optional. However in the process I also changed pointers or functions singatures a lot. (not really necessary it turns out) See this branch:
https://github.com/mugr1x/osrm/tree/boost_optional_old
If you change the heap::increase call to heap::decrease at least it does not segfault anymore.
Also I probably should do a cleanup.