- __cdecl
- Standard/default calling convention in Unix/Win32
- Caller should push and pop the arguments (right to left)
- Variable number of argument functions such as printf, scanf can be used with because the callee cannot know the number of parameters
- Freeing stack Instructions are inserted after every call of the function, so it increases the code size if many calls are made
- __stdcall/PASCAL
- Microsoft Win32 supported
- Arguments are pushed (left to right) by the called and stack is cleaned up by the callee
- No variable number of argument functions are allowed
- Conserve some code space (one time cleanup by callee)
- __fastcall
- Microsoft Win32 supported
- Registers are used for passing arguments
- The registers are pushed to and popped from the stack (first two arguments are copied into the registers, the rest should resort to the stack by_stdcall fashion)
- Bit overhead
- Used for local functions within the module
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