diff --git a/winsup/cygwin/mmap.cc b/winsup/cygwin/mmap.cc
index d8ef037f0..662489c8c 100644
--- a/winsup/cygwin/mmap.cc
+++ b/winsup/cygwin/mmap.cc
@@ -1466,9 +1466,6 @@ munlock (const void *addr, size_t len)
   return ret;
 }
 
-/* This is required until Mingw-w64 catches up with newer functions. */
-extern "C" WINAPI DWORD DiscardVirtualMemory (PVOID, SIZE_T);
-
 extern "C" int
 posix_madvise (void *addr, size_t len, int advice)
 {
diff --git a/winsup/cygwin/uinfo.cc b/winsup/cygwin/uinfo.cc
index bfcce00da..2d5de359b 100644
--- a/winsup/cygwin/uinfo.cc
+++ b/winsup/cygwin/uinfo.cc
@@ -1912,9 +1912,6 @@ pwdgrp::construct_sid_from_name (cygsid &sid, wchar_t *name, wchar_t *sep)
   return false;
 }
 
-/* CV 2018-08-28: SidTypeLogonSession is not yet defined in Mingw64. */
-#define SidTypeLogonSession 11
-
 char *
 pwdgrp::fetch_account_from_windows (fetch_user_arg_t &arg, cyg_ldap *pldap)
 {
diff --git a/winsup/cygwin/winlean.h b/winsup/cygwin/winlean.h
index 1332cb7aa..9b30b6557 100644
--- a/winsup/cygwin/winlean.h
+++ b/winsup/cygwin/winlean.h
@@ -94,15 +94,4 @@ details. */
 #define GetWindowsDirectoryW dont_use_GetWindowsDirectory
 #define GetWindowsDirectoryA dont_use_GetWindowsDirectory
 
-/* For console with xterm compatible mode */
-/* Not yet defined in Mingw-w64 */
-#ifndef ENABLE_VIRTUAL_TERMINAL_PROCESSING
-#define ENABLE_VIRTUAL_TERMINAL_PROCESSING 0x0004
-#endif /* ENABLE_VIRTUAL_TERMINAL_PROCESSING */
-#ifndef ENABLE_VIRTUAL_TERMINAL_INPUT
-#define ENABLE_VIRTUAL_TERMINAL_INPUT 0x0200
-#endif /* ENABLE_VIRTUAL_TERMINAL_INPUT */
-#ifndef DISABLE_NEWLINE_AUTO_RETURN
-#define DISABLE_NEWLINE_AUTO_RETURN 0x0008
-#endif /* DISABLE_NEWLINE_AUTO_RETURN */
 #endif /*_WINLEAN_H*/