diff --git a/include/wx/propgrid/propgriddefs.h b/include/wx/propgrid/propgriddefs.h
index 59a936fdba..717af47696 100644
--- a/include/wx/propgrid/propgriddefs.h
+++ b/include/wx/propgrid/propgriddefs.h
@@ -400,16 +400,16 @@ enum wxPG_SETVALUE_FLAGS
 //
 // Valid constants for wxPG_UINT_BASE attribute
 // (long because of wxVariant constructor)
-#define wxPG_BASE_OCT                       (long)8
-#define wxPG_BASE_DEC                       (long)10
-#define wxPG_BASE_HEX                       (long)16
-#define wxPG_BASE_HEXL                      (long)32
+#define wxPG_BASE_OCT                       8L
+#define wxPG_BASE_DEC                       10L
+#define wxPG_BASE_HEX                       16L
+#define wxPG_BASE_HEXL                      32L
 
 //
 // Valid constants for wxPG_UINT_PREFIX attribute
-#define wxPG_PREFIX_NONE                    (long)0
-#define wxPG_PREFIX_0x                      (long)1
-#define wxPG_PREFIX_DOLLAR_SIGN             (long)2
+#define wxPG_PREFIX_NONE                    0L
+#define wxPG_PREFIX_0x                      1L
+#define wxPG_PREFIX_DOLLAR_SIGN             2L
 
 // -----------------------------------------------------------------------
 // Editor class.
diff --git a/interface/wx/propgrid/propgriddefs.h b/interface/wx/propgrid/propgriddefs.h
index c475c39542..c6b4c00db6 100644
--- a/interface/wx/propgrid/propgriddefs.h
+++ b/interface/wx/propgrid/propgriddefs.h
@@ -182,17 +182,18 @@ enum wxPG_SETVALUE_FLAGS
 // -----------------------------------------------------------------------
 
 //
-// Valid constants for wxPG_UINT_BASE attribute
-// (long because of wxVariant constructor)
-#define wxPG_BASE_OCT                       (long)8
-#define wxPG_BASE_DEC                       (long)10
-#define wxPG_BASE_HEX                       (long)16
-#define wxPG_BASE_HEXL                      (long)32
+/** Valid constants for ::wxPG_UINT_BASE attribute
+    (@c long because of wxVariant constructor)
+*/
+#define wxPG_BASE_OCT                       8L
+#define wxPG_BASE_DEC                       10L
+#define wxPG_BASE_HEX                       16L
+#define wxPG_BASE_HEXL                      32L
 
-//
-// Valid constants for wxPG_UINT_PREFIX attribute
-#define wxPG_PREFIX_NONE                    (long)0
-#define wxPG_PREFIX_0x                      (long)1
-#define wxPG_PREFIX_DOLLAR_SIGN             (long)2
+/** Valid constants for ::wxPG_UINT_PREFIX attribute
+*/
+#define wxPG_PREFIX_NONE                    0L
+#define wxPG_PREFIX_0x                      1L
+#define wxPG_PREFIX_DOLLAR_SIGN             2L
 
 // -----------------------------------------------------------------------
diff --git a/src/propgrid/propgrid.cpp b/src/propgrid/propgrid.cpp
index 3da6d3df0e..e8d6ba5edf 100644
--- a/src/propgrid/propgrid.cpp
+++ b/src/propgrid/propgrid.cpp
@@ -185,8 +185,8 @@ wxPGGlobalVarsClass* wxPGGlobalVars = NULL;
 wxPGGlobalVarsClass::wxPGGlobalVarsClass()
     // Prepare some shared variants
     : m_vEmptyString(wxString())
-    , m_vZero((long)0)
-    , m_vMinusOne((long)-1)
+    , m_vZero(0L)
+    , m_vMinusOne(-1L)
     , m_vTrue(true)
     , m_vFalse(false)
     // Prepare cached string constants