This comes up repeatedly in SO questions, I’ll try to turn this into a (long) reference answer. 32-bit code is saddled with a long history of incompatible calling conventions. Choices on how to make a function call that made sense a long time ago but are mostly a giant pain in the rear end today. … Read more
Raymond Chen gives a nice overview of what __stdcall and __cdecl does. (1) The caller “knows” to clean up the stack after calling a function because the compiler knows the calling convention of that function and generates the necessary code. void __stdcall StdcallFunc() {} void __cdecl CdeclFunc() { // The compiler knows that StdcallFunc() uses … Read more
__stdcall is the calling convention used for the function. This tells the compiler the rules that apply for setting up the stack, pushing arguments and getting a return value. There are a number of other calling conventions, __cdecl, __thiscall, __fastcall and the wonderfully named __declspec(naked). __stdcall is the standard calling convention for Win32 system calls. … Read more