These warnings have not been fixed because the are legitimate and/or I don't know how to fix them:
test\googletest\googletest\include\gtest/gtest-printers.h(888,43): warning C4996: 'std::tr1': warning STL4002: The non-Standard std::tr1 namespace and TR1-only machinery are deprecated and will be REMOVED.
lib\serializer\JsonSerializeFormat.h(523,26): warning C4244: 'argument': conversion from 'type1' to 'type2', possible loss of data
include\boost/iostreams/positioning.hpp(96,15): warning C4996: 'std::fpos<_Mbstatet>::seekpos': warning STL4019: The member std::fpos::seekpos() is non-Standard, ...
source\lib\filesystem\FileStream.h(39,69): warning C4910: 'boost::iostreams::stream<FileBuf,std::char_traits<char>,std::allocator<char>>': '__declspec(dllexport)' and 'extern' are incompatible on an explicit instantiation
include\boost/optional/optional.hpp(274,53): warning C4244: 'argument': conversion from 'T' to 'T', possible loss of data
client\widgets\../gui/SDL_Extensions.h(112,14): warning C4244: 'initializing': conversion from 'type1' to 'type2', possible loss of data
client\CServerHandler.cpp(421,24): warning C4834: discarding return value of function with 'nodiscard' attribute (see https://bugs.vcmi.eu/view.php?id=3144)
client\CVideoHandler.cpp(130,25): warning C4996: 'AVStream::codec': was declared deprecated
Warnings fixes
* Suppress `missing-braces` for Clang
* Fixed many C4275 warnings
* Fixed almost all Clang/GCC warnings
* Silence most frequent MSVC warning.
* Fixed some pessimizing-move warnings
* Fixed some unused capture warnings
* Indirect spell effects loading
* Json serializer improvements
* spell->canBeCastAt do not allow useless cast for any spell
* Added proxy caster class for spell-created obstacles
* Handle damage from spell-created obstacles inside mechanics
* Experimental GameState integration/regression tests
* Ignore mod settings and load only "vcmi" mod when running tests
* fixed https://bugs.vcmi.eu/view.php?id=2765 (with tests)
* Huge improvements of BattleAI regarding spell casts
* AI can cast almost any combat spell except TELEPORT, SACRIFICE and obstacle placement spells.
* Possible fix for https://bugs.vcmi.eu/view.php?id=1811
* CStack factored out to several classes
* [Battle] Allowed RETURN_AFTER_STRIKE effect on server side to be optional
* [Battle] Allowed BattleAction have multiple destinations
* [Spells] Converted limit|immunity to target condition
* [Spells] Use partial configuration reload for backward compatibility handling
* [Tests] Started tests for CUnitState
* Partial fixes of fire shield effect
* [Battle] Do HP calculations in 64 bits
* [BattleAI] Use threading for spell cast evaluation
* [BattleAI] Made AI be able to evaluate modified turn order (on hypothetical battle state)
* Implemented https://bugs.vcmi.eu/view.php?id=2811
* plug rare freeze when hypnotized unit shots vertically
* Correctly apply ONLY_MELEE_FIGHT / ONLY_DISTANCE_FIGHT for unit damage, attack & defense
* [BattleAI] Try to not waste a cast if battle is actually won already
* Extended JsonSerializeFormat API
* fixed https://bugs.vcmi.eu/view.php?id=2847
* Any unit effect can be now chained (not only damage like Chain Lightning)
** only damage effect for now actually uses "chainFactor"
* Possible quick fix for https://bugs.vcmi.eu/view.php?id=2860