diff --git a/mingw-w64-tools/widl/VERSION b/mingw-w64-tools/widl/VERSION
index 5e11b9e..6bd6909 100644
--- a/mingw-w64-tools/widl/VERSION
+++ b/mingw-w64-tools/widl/VERSION
@@ -1 +1 @@
-WIDL version 1.5.29
+WIDL version 1.5.31
diff --git a/mingw-w64-tools/widl/configure b/mingw-w64-tools/widl/configure
index ece0ebc..66aa709 100755
--- a/mingw-w64-tools/widl/configure
+++ b/mingw-w64-tools/widl/configure
@@ -1,6 +1,6 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.69 for widl 1.5.29.
+# Generated by GNU Autoconf 2.69 for widl 1.5.31.
 #
 # Report bugs to <mingw-w64-public@lists.sourceforge.net>.
 #
@@ -580,8 +580,8 @@
 # Identity of this package.
 PACKAGE_NAME='widl'
 PACKAGE_TARNAME='widl'
-PACKAGE_VERSION='1.5.29'
-PACKAGE_STRING='widl 1.5.29'
+PACKAGE_VERSION='1.5.31'
+PACKAGE_STRING='widl 1.5.31'
 PACKAGE_BUGREPORT='mingw-w64-public@lists.sourceforge.net'
 PACKAGE_URL=''
 
@@ -1278,7 +1278,7 @@
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures widl 1.5.29 to adapt to many kinds of systems.
+\`configure' configures widl 1.5.31 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1349,7 +1349,7 @@
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of widl 1.5.29:";;
+     short | recursive ) echo "Configuration of widl 1.5.31:";;
    esac
   cat <<\_ACEOF
 
@@ -1441,7 +1441,7 @@
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-widl configure 1.5.29
+widl configure 1.5.31
 generated by GNU Autoconf 2.69
 
 Copyright (C) 2012 Free Software Foundation, Inc.
@@ -1994,7 +1994,7 @@
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by widl $as_me 1.5.29, which was
+It was created by widl $as_me 1.5.31, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   $ $0 $@
@@ -2933,7 +2933,7 @@
 
 # Define the identity of the package.
  PACKAGE='widl'
- VERSION='1.5.29'
+ VERSION='1.5.31'
 
 
 cat >>confdefs.h <<_ACEOF
@@ -5493,7 +5493,7 @@
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by widl $as_me 1.5.29, which was
+This file was extended by widl $as_me 1.5.31, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
@@ -5559,7 +5559,7 @@
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
 ac_cs_version="\\
-widl config.status 1.5.29
+widl config.status 1.5.31
 configured by $0, generated by GNU Autoconf 2.69,
   with options \\"\$ac_cs_config\\"
 
diff --git a/mingw-w64-tools/widl/include/winbase.h b/mingw-w64-tools/widl/include/winbase.h
index ad51af3..4e21049 100644
--- a/mingw-w64-tools/widl/include/winbase.h
+++ b/mingw-w64-tools/widl/include/winbase.h
@@ -1951,6 +1951,8 @@
 WINADVAPI  BOOL        WINAPI InitializeSid(PSID,PSID_IDENTIFIER_AUTHORITY,BYTE);
 WINBASEAPI VOID        WINAPI InitializeSListHead(PSLIST_HEADER);
 WINBASEAPI VOID        WINAPI InitializeSRWLock(PSRWLOCK);
+WINBASEAPI BOOL        WINAPI InitOnceBeginInitialize(PINIT_ONCE, DWORD, PBOOL, PVOID*);
+WINBASEAPI BOOL        WINAPI InitOnceComplete(PINIT_ONCE, DWORD, PVOID);
 WINBASEAPI BOOL        WINAPI InitOnceExecuteOnce(PINIT_ONCE,PINIT_ONCE_FN,PVOID,PVOID*);
 WINBASEAPI VOID        WINAPI InitOnceInitialize(PINIT_ONCE);
 WINBASEAPI PSLIST_ENTRY WINAPI InterlockedFlushSList(PSLIST_HEADER);
diff --git a/mingw-w64-tools/widl/include/winnt.h b/mingw-w64-tools/widl/include/winnt.h
index 6911f1c..171141e 100644
--- a/mingw-w64-tools/widl/include/winnt.h
+++ b/mingw-w64-tools/widl/include/winnt.h
@@ -5163,6 +5163,8 @@
 typedef RTL_RUN_ONCE_INIT_FN *PRTL_RUN_ONCE_INIT_FN;
 NTSYSAPI VOID WINAPI RtlRunOnceInitialize(PRTL_RUN_ONCE);
 NTSYSAPI DWORD WINAPI RtlRunOnceExecuteOnce(PRTL_RUN_ONCE,PRTL_RUN_ONCE_INIT_FN,PVOID,PVOID*);
+NTSYSAPI DWORD WINAPI RtlRunOnceBeginInitialize(PRTL_RUN_ONCE, DWORD, PBOOL, PVOID*);
+NTSYSAPI DWORD WINAPI RtlRunOnceComplete(PRTL_RUN_ONCE, DWORD, PVOID);
 
 #include <pshpack8.h>
 typedef struct _IO_COUNTERS {