-PIMAGE_NT_HEADERS
-(__stdcall * pfnCheckSumMappedFile) (LPVOID BaseAddress, DWORD FileLength,
- LPDWORD HeaderSum, LPDWORD CheckSum);
+typedef PIMAGE_NT_HEADERS
+(__stdcall * pfnCheckSumMappedFile_t) (LPVOID BaseAddress, DWORD FileLength,
+ LPDWORD HeaderSum, LPDWORD CheckSum);
+