clang vs cl double definition

console output

clang-cl main.cpp -c -o main.o
In file included from main.cpp:3:
./win32.h(29,21):  error: conflicting types for 'GetCursorPos'
WIN32_IMPORT(BOOL)              GetCursorPos(LPPOINT lpPoint);
                                ^
C:\Program Files (x86)\Windows Kits\10\include\10.0.16299.0\um\winuser.h(9110,1):  note: previous declaration is here
GetCursorPos(
^
1 error generated.

cl main.cpp
Microsoft (R) C/C++ Optimizing Compiler Version 19.12.25834 for x64
Copyright (C) Microsoft Corporation.  All rights reserved.

main.cpp
Microsoft (R) Incremental Linker Version 14.12.25834.0
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:main.exe
main.obj

fakemake.bat

clang-cl main.cpp -c -o main.o
cl main.cpp

main.cpp

#include<stdio.h>
#include<windows.h>
#include "win32.h"

int main(void) {
	printf("Hello World");
}

win32.h

#pragma once
#include<stdint.h>

#ifdef __VISUAL_C__
#pragma comment(lib, "comctl32.lib")
#endif

// Win32 Import calling conventions
#define WIN32_API					__stdcall
#define WIN32_IMPORT(inReturnType)	__declspec(dllimport) inReturnType WIN32_API

//---------------------------------------------------------------------------------------------------------------------
//	Win32 namespace
//---------------------------------------------------------------------------------------------------------------------

namespace Win32 {
extern "C" { 

typedef int 							BOOL;
typedef int32_t							LONG;

struct POINT
{
	LONG				x;
	LONG				y;
};
typedef POINT			*LPPOINT;

WIN32_IMPORT(BOOL)		GetCursorPos(LPPOINT lpPoint);
}}