--- a/taskcluster/scripts/misc/build-clang-7-pre-mingw.sh
+++ b/taskcluster/scripts/misc/build-clang-7-pre-mingw.sh
@@ -35,16 +35,17 @@ prepare() {
   touch $TOOLCHAIN_DIR/.build-clang
 
   mkdir -p $SRC_DIR
   pushd $SRC_DIR
 
   git clone -n git://git.code.sf.net/p/mingw-w64/mingw-w64
   pushd mingw-w64
   git checkout $mingw_version
+  patch -p1 <  $HOME_DIR/src/taskcluster/scripts/misc/mingw-error-codes.patch
   popd
 
   git clone https://github.com/llvm-mirror/libunwind.git
   pushd libunwind
   git checkout $libunwind_version
   popd
 
   wget -c --progress=dot:mega ftp://ftp.gnu.org/gnu/binutils/binutils-$binutils_version.tar.$binutils_ext

new file mode 100644
--- /dev/null
+++ b/taskcluster/scripts/misc/mingw-error-codes.patch
@@ -0,0 +1,48 @@
+From 71ee4edf14d76ddacb8154620024c7a8b60be18b Mon Sep 17 00:00:00 2001
+From: Tom Ritter <tom@ritter.vg>
+Date: Thu, 2 Aug 2018 09:50:56 -0500
+Subject: [PATCH] Add Error Codes between 1460 and 1471
+
+---
+ mingw-w64-headers/include/winerror.h    | 9 +++++++++
+ mingw-w64-tools/widl/include/winerror.h | 1 +
+ 2 files changed, 10 insertions(+)
+ mode change 100644 => 100755 mingw-w64-headers/include/winerror.h
+
+diff --git a/mingw-w64-headers/include/winerror.h b/mingw-w64-headers/include/winerror.h
+old mode 100644
+new mode 100755
+index e117b046..5eba03f6
+--- a/mingw-w64-headers/include/winerror.h
++++ b/mingw-w64-headers/include/winerror.h
+@@ -631,6 +631,15 @@
+ #define ERROR_TIMEOUT __MSABI_LONG(1460)
+ #define ERROR_INVALID_MONITOR_HANDLE __MSABI_LONG(1461)
+ #define ERROR_INCORRECT_SIZE __MSABI_LONG(1462)
++#define ERROR_SYMLINK_CLASS_DISABLED __MSABI_LONG(1463)
++#define ERROR_SYMLINK_NOT_SUPPORTED __MSABI_LONG(1464)
++#define ERROR_XML_PARSE_ERROR __MSABI_LONG(1465)
++#define ERROR_XMLDSIG_ERROR __MSABI_LONG(1466)
++#define ERROR_RESTART_APPLICATION __MSABI_LONG(1467)
++#define ERROR_WRONG_COMPARTMENT __MSABI_LONG(1468)
++#define ERROR_AUTHIP_FAILURE __MSABI_LONG(1469)
++#define ERROR_NO_NVRAM_RESOURCES __MSABI_LONG(1470)
++#define ERROR_NOT_GUI_PROCESS __MSABI_LONG(1471)
+ #define ERROR_EVENTLOG_FILE_CORRUPT __MSABI_LONG(1500)
+ #define ERROR_EVENTLOG_CANT_START __MSABI_LONG(1501)
+ #define ERROR_LOG_FILE_FULL __MSABI_LONG(1502)
+diff --git a/mingw-w64-tools/widl/include/winerror.h b/mingw-w64-tools/widl/include/winerror.h
+index 2c6ce20b..180e3efe 100644
+--- a/mingw-w64-tools/widl/include/winerror.h
++++ b/mingw-w64-tools/widl/include/winerror.h
+@@ -940,6 +940,7 @@ static inline HRESULT HRESULT_FROM_WIN32(unsigned int x)
+ #define ERROR_WRONG_COMPARTMENT                            1468
+ #define ERROR_AUTHIP_FAILURE                               1469
+ #define ERROR_NO_NVRAM_RESOURCES                           1470
++#define ERROR_NOT_GUI_PROCESS                              1471
+ #define ERROR_EVENTLOG_FILE_CORRUPT                        1500
+ #define ERROR_EVENTLOG_CANT_START                          1501
+ #define ERROR_LOG_FILE_FULL                                1502
+-- 
+2.17.1
+