diff --git a/src/lib/arch/win32/ArchSystemWindows.cpp b/src/lib/arch/win32/ArchSystemWindows.cpp
index 654c92d1..cf3b0669 100644
--- a/src/lib/arch/win32/ArchSystemWindows.cpp
+++ b/src/lib/arch/win32/ArchSystemWindows.cpp
@@ -141,7 +141,7 @@ ArchSystemWindows::getLibsUsed(void) const
 
     DWORD pid = GetCurrentProcessId();
 
-    std::string msg = "pid:" + std::to_string((_ULonglong)pid) + "\n";
+    std::string msg = "pid:" + std::to_string((unsigned long long)pid) + "\n";
 
     hProcess = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ, FALSE, pid);