gcc-dev_unity_xtra warnings for Arx in branch master

• -Wconditionally-supported [docs] (1 | =)
• -Wmaybe-uninitialized [docs] (3 | +3)
• -Wsuggest-final-types [docs] (3 | +3)
• -Wstrict-aliasing [docs] (6 | =)
• -Wunused-const-variable= [docs] (9 | +9)
• -Wsuggest-final-methods [docs] (10 | +10)
• -Wuseless-cast [docs] (27 | -11)
• -Wold-style-cast [docs] (102 | =)
• -Wpadded [docs] (295 | =)
• -Wconversion [docs] (408 | +17 -3)
• -Wzero-as-null-pointer-constant [docs] (711 | =)