diff --git a/mingw-w64-hclient/.gitignore b/mingw-w64-hclient/.gitignore
new file mode 100644
index 0000000000..5c6fb78c8c
--- /dev/null
+++ b/mingw-w64-hclient/.gitignore
@@ -0,0 +1 @@
+wds
diff --git a/mingw-w64-hclient/01-includes.patch b/mingw-w64-hclient/01-includes.patch
new file mode 100644
index 0000000000..18ee7dda8a
--- /dev/null
+++ b/mingw-w64-hclient/01-includes.patch
@@ -0,0 +1,11 @@
+--- a/buffers.h
++++ b/buffers.h
+@@ -24,6 +24,8 @@ Revision History:
+ #ifndef _BUFFERS_H_
+ #define _BUFFERS_H_
+ 
++#include <sal.h>
++
+ typedef struct _REPORT_BUFFER
+ {
+     _Field_size_(iBufferSize) 
diff --git a/mingw-w64-hclient/02-intsafe.patch b/mingw-w64-hclient/02-intsafe.patch
new file mode 100644
index 0000000000..8266340dd0
--- /dev/null
+++ b/mingw-w64-hclient/02-intsafe.patch
@@ -0,0 +1,11 @@
+--- a/buffers.c
++++ b/buffers.c
+@@ -79,7 +79,7 @@
+         return (FALSE);
+     }
+ 
+-    if(S_OK != ULongMult(sizeof(REPORT_BUFFER), nBuffers, &reportBuffersSize))
++    if(__builtin_mul_overflow(sizeof(REPORT_BUFFER), nBuffers, &reportBuffersSize))
+     {
+         free(pNewDisplay);
+         return (FALSE);
diff --git a/mingw-w64-hclient/03-read-thread-proc.patch b/mingw-w64-hclient/03-read-thread-proc.patch
new file mode 100644
index 0000000000..4cf0c35ead
--- /dev/null
+++ b/mingw-w64-hclient/03-read-thread-proc.patch
@@ -0,0 +1,45 @@
+--- a/hclient.c
++++ b/hclient.c
+@@ -3692,10 +3692,10 @@ DestroyDeviceListCallback(
+ }
+ 
+ DWORD WINAPI
+-AsynchReadThreadProc( 
+-    PREAD_THREAD_CONTEXT    Context
+-)
++AsynchReadThreadProc(
++    LPVOID c)
+ {
++    PREAD_THREAD_CONTEXT Context = c;
+     HANDLE  completionEvent;
+     BOOL    readStatus;
+     DWORD   waitStatus;
+@@ -3818,9 +3818,9 @@ AsyncRead_End:
+ 
+ DWORD WINAPI
+ SynchReadThreadProc(
+-    PREAD_THREAD_CONTEXT    Context
+-)
++    LPVOID c)
+ {
++    PREAD_THREAD_CONTEXT Context = c;
+     ULONG   numReadsDone = 0;
+     do 
+     {
+--- a/hclient.h
++++ b/hclient.h
+@@ -140,12 +140,12 @@ vDisplayValueAttributes(
+ 
+ DWORD WINAPI
+ AsynchReadThreadProc(
+-    PREAD_THREAD_CONTEXT    Context
++    LPVOID
+ );
+ 
+ DWORD WINAPI
+ SynchReadThreadProc(
+-    PREAD_THREAD_CONTEXT    Context
++    LPVOID
+ );
+ 
+ #endif
diff --git a/mingw-w64-hclient/04-bad-comparison.patch b/mingw-w64-hclient/04-bad-comparison.patch
new file mode 100644
index 0000000000..e62ddfe3cc
--- /dev/null
+++ b/mingw-w64-hclient/04-bad-comparison.patch
@@ -0,0 +1,11 @@
+--- a/hclient.c
++++ b/hclient.c
+@@ -3560,7 +3560,7 @@ Routine Description:
+     //
+     if(iByteIndex + (UINT)4 > uiBufferSize)
+     {
+-        if(sizeof(szString) <= uiStringSize)
++
+         {
+             StringCbPrintf(szString, uiStringSize, "ERR");
+         }
diff --git a/mingw-w64-hclient/05-other-bad-comparison.patch b/mingw-w64-hclient/05-other-bad-comparison.patch
new file mode 100644
index 0000000000..fc64b24e52
--- /dev/null
+++ b/mingw-w64-hclient/05-other-bad-comparison.patch
@@ -0,0 +1,11 @@
+--- a/strings.c
++++ b/strings.c
+@@ -196,7 +196,7 @@ Routine Description:
+                 goto Done;
+             } 
+ 
+-            if(ByteOffset + DataBuffer > CurrentBufferOffset+ByteOffset)
++            if(ByteOffset + DataBuffer > (PCHAR)CurrentBufferOffset+ByteOffset)
+             {
+                 goto Done;
+             }
diff --git a/mingw-w64-hclient/06-size-t.patch b/mingw-w64-hclient/06-size-t.patch
new file mode 100644
index 0000000000..ce58bce400
--- /dev/null
+++ b/mingw-w64-hclient/06-size-t.patch
@@ -0,0 +1,11 @@
+--- a/ecdisp.c
++++ b/ecdisp.c
+@@ -155,7 +155,7 @@
+ #define OUTSTRING(win, str)         SendMessage(win, LB_ADDSTRING, 0, (LPARAM) str)
+ #define OUTWSTRING(win, str) \
+ { \
+-    SIZE_T  nBytes; \
++    size_t  nBytes; \
+ \
+     errno_t result = wcstombs_s(&nBytes, szTempBuffer, TEMP_BUFFER_SIZE, str, TEMP_BUFFER_SIZE-1); \
+     if (0 != result) { \
diff --git a/mingw-w64-hclient/07-dialog-proc.patch b/mingw-w64-hclient/07-dialog-proc.patch
new file mode 100644
index 0000000000..7a8fccae75
--- /dev/null
+++ b/mingw-w64-hclient/07-dialog-proc.patch
@@ -0,0 +1,168 @@
+--- a/ecdisp.c
++++ b/ecdisp.c
+@@ -499,7 +499,7 @@
+     OUT INT               *nReportIDs
+ );
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetUsagesDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -507,7 +507,7 @@
+     LPARAM lParam
+ );
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetValueDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -515,7 +515,7 @@
+     LPARAM lParam
+ );
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetInputBuffDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -523,7 +523,7 @@
+     LPARAM lParam
+ );
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetDataDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -531,7 +531,7 @@
+     LPARAM lParam
+ );
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetBufLenDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -539,7 +539,7 @@
+     LPARAM lParam
+ );
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetInputBuffersDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -547,7 +547,7 @@
+     LPARAM lParam
+ );
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bGetIndexedDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -555,7 +555,7 @@
+     LPARAM lParam
+ );
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bGetUsageDiffDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -629,7 +629,7 @@
+ /* Global function definitions
+ /*****************************************************************************/
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bExtCallDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -3313,7 +3313,7 @@
+     return;
+ }
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetUsagesDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -3378,7 +3378,7 @@
+     return (FALSE);
+ }
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetValueDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -3449,7 +3449,7 @@
+     return (FALSE);
+ }
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetInputBuffDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -3510,7 +3510,7 @@
+     return (FALSE);
+ }
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetDataDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -3687,7 +3687,7 @@
+     return (FALSE);
+ }
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetBufLenDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -3749,7 +3749,7 @@
+     return (FALSE);
+ }
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bSetInputBuffersDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -3810,7 +3810,7 @@
+     return (FALSE);
+ }
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bGetIndexedDlgProc(
+     HWND hDlg,
+     UINT message,
+@@ -3883,7 +3883,7 @@
+     return (FALSE);
+ }
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bGetUsageDiffDlgProc(
+     HWND hDlg,
+     UINT message,
+diff --git a/hid/hclient/ecdisp.h b/hid/hclient/ecdisp.h
+index ea0bd0f..6d13b83 100644
+--- a/ecdisp.h
++++ b/ecdisp.h
+@@ -71,7 +71,7 @@
+ /* Global Extended Call display function declarations
+ /*****************************************************************************/
+ 
+-LRESULT CALLBACK
++INT_PTR CALLBACK
+ bExtCallDlgProc(
+     HWND   hDlg,
+     UINT   message,
diff --git a/mingw-w64-hclient/PKGBUILD b/mingw-w64-hclient/PKGBUILD
new file mode 100644
index 0000000000..bf310a3969
--- /dev/null
+++ b/mingw-w64-hclient/PKGBUILD
@@ -0,0 +1,88 @@
+# Maintainer: David Grayson <davidegrayson@gmail.com>
+
+_realname=hclient
+pkgbase=mingw-w64-${_realname}
+pkgname="${MINGW_PACKAGE_PREFIX}-${_realname}-git"
+provides="${MINGW_PACKAGE_PREFIX}-${_realname}"
+conflicts="${MINGW_PACKAGE_PREFIX}-${_realname}"
+pkgver=37.efd8c0a
+pkgrel=1
+pkgdesc='Sample GUI for communicating with HIDs (mingw-w64)'
+arch=('any')
+url='https://github.com/Microsoft/Windows-driver-samples/tree/master/hid/hclient'
+license=('custom')
+makedepends=("${MINGW_PACKAGE_PREFIX}-gcc")
+depends=()
+options=('strip')
+source=(
+  "wds::git+https://github.com/Microsoft/Windows-driver-samples"
+  '01-includes.patch'
+  '02-intsafe.patch'
+  '03-read-thread-proc.patch'
+  '04-bad-comparison.patch'
+  '05-other-bad-comparison.patch'
+  '06-size-t.patch'
+  '07-dialog-proc.patch'
+)
+
+sha256sums=('SKIP'
+            'c5e16ddaa76e5d2dbcf3d8b5083f9a2dfca74f869419c2e5be9b7444b05a72db'
+            '6c73b234ff46a20cae7de86e6d96f53629624c9b3d005d72030500e95616b826'
+            '6f2f2ffe160cf71c43fb0224efabf045490ef0202921600f79c45b0bab527e45'
+            '8c879599a1cf95ed838be8030acb2d74d85989de10a61c7ac1e9243266d1c361'
+            'e673215729689b21fd4b6b246e70ed4a8d75fea871dac6b0ec410bf4fc87d60c'
+            '94b4ebd39a372cf105d45daa1be9c5286dc307a82325273c9925253985c736c8'
+            'c2caed5841c2212ec43b7799b0140fcdd5e217b0488f8cfe9318a19841e0eb32')
+
+pkgver() {
+  cd "${srcdir}/wds"
+  printf "%s.%s" "$(git rev-list --count HEAD)" "$(git rev-parse --short HEAD)"
+}
+
+prepare() {
+  cd "${srcdir}/wds/hid/${_realname}"
+
+  patch -p1 -i "${srcdir}/01-includes.patch"
+
+  # GCC distinguishes between unsigned long and unsigned int.
+  patch -p1 -i "${srcdir}/02-intsafe.patch"
+
+  # GCC distinguishes between void pointers and other pointers.
+  patch -p1 -i "${srcdir}/03-read-thread-proc.patch"
+
+  # GCC warns about this because sizeof() for an array parameter
+  # just returns the size of a pointer.
+  patch -p1 -i "${srcdir}/04-bad-comparison.patch"
+
+  # Fix a compile warning from comparing two different pointer types without a
+  # cast.
+  patch -p1 -i "${srcdir}/05-other-bad-comparison.patch"
+
+  # size_t is different from SIZE_T
+  patch -p1 -i "${srcdir}/06-size-t.patch"
+
+  # DlgProcs are supposed to return INT_PTR, which is different from LRESULT.
+  patch -p1 -i "${srcdir}/07-dialog-proc.patch"
+}
+
+build() {
+  cd "${srcdir}"
+  rm -rf "build-${MINGW_CHOST}"
+  mkdir -p "build-${MINGW_CHOST}"
+  cd "build-${MINGW_CHOST}"
+
+  windres ../wds/hid/hclient/hclient.rc rc.so
+
+  gcc -mwindows --std=c99 ${CFLAGS} ${LDFLAGS} \
+    ../wds/hid/hclient/*.c rc.so \
+    -lsetupapi -lhid \
+    -o hclient.exe
+}
+
+package() {
+  cd "${srcdir}/wds"
+  install -Dm644 LICENSE "${pkgdir}${MINGW_PREFIX}/share/licenses/${_realname}/LICENSE"
+  cd "${srcdir}/build-${MINGW_CHOST}"
+  mkdir "${pkgdir}${MINGW_PREFIX}/bin"
+  install -Dm755 hclient.exe "${pkgdir}${MINGW_PREFIX}/bin"
+}