diff --git a/var/spack/repos/builtin/packages/qt/package.py b/var/spack/repos/builtin/packages/qt/package.py
index 8e0c89f538c..0337f6be677 100644
--- a/var/spack/repos/builtin/packages/qt/package.py
+++ b/var/spack/repos/builtin/packages/qt/package.py
@@ -73,6 +73,7 @@ class Qt(Package):
 
     patch('qt3accept.patch', when='@3.3.8b')
     patch('qt3krell.patch', when='@3.3.8b+krellpatch')
+    patch('qt3ptrdiff.patch', when='@3.3.8b')
 
     # see https://bugreports.qt.io/browse/QTBUG-57656
     patch('QTBUG-57656.patch', when='@5.8.0')
diff --git a/var/spack/repos/builtin/packages/qt/qt3ptrdiff.patch b/var/spack/repos/builtin/packages/qt/qt3ptrdiff.patch
new file mode 100644
index 00000000000..5043e4b5a88
--- /dev/null
+++ b/var/spack/repos/builtin/packages/qt/qt3ptrdiff.patch
@@ -0,0 +1,20 @@
+--- a/src/tools/qmap.h	2008-01-16 06:09:13.000000000 +1100
++++ b/src/tools/qmap.h	2018-01-07 11:32:38.720893324 +1100
+@@ -52,6 +52,7 @@
+ #ifndef QT_NO_STL
+ #include <iterator>
+ #include <map>
++#include <stddef.h>
+ #endif
+ 
+ //#define QT_CHECK_MAP_RANGE
+--- a/src/tools/qvaluelist.h	2008-01-16 06:09:13.000000000 +1100
++++ b/src/tools/qvaluelist.h	2018-01-07 11:33:03.393206961 +1100
+@@ -50,6 +50,7 @@
+ #ifndef QT_NO_STL
+ #include <iterator>
+ #include <list>
++#include <stddef.h>
+ #endif
+ 
+ //#define QT_CHECK_VALUELIST_RANGE