diff --git a/include/wx/ffile.h b/include/wx/ffile.h
index ba0f440181..954a700387 100644
--- a/include/wx/ffile.h
+++ b/include/wx/ffile.h
@@ -118,7 +118,7 @@ public:
     // default
   wxTempFFile() { }
     // associates the temp file with the file to be replaced and opens it
-  wxTempFFile(const wxString& strName);
+  explicit wxTempFFile(const wxString& strName);
 
   // open the temp file (strName is the name of file to be replaced)
   bool Open(const wxString& strName);
diff --git a/include/wx/file.h b/include/wx/file.h
index 282994c87e..8a6faba06e 100644
--- a/include/wx/file.h
+++ b/include/wx/file.h
@@ -147,7 +147,7 @@ public:
     // default
   wxTempFile() { }
     // associates the temp file with the file to be replaced and opens it
-  wxTempFile(const wxString& strName);
+  explicit wxTempFile(const wxString& strName);
 
   // open the temp file (strName is the name of file to be replaced)
   bool Open(const wxString& strName);
diff --git a/interface/wx/ffile.h b/interface/wx/ffile.h
index 0252a2589c..75a9df5260 100644
--- a/interface/wx/ffile.h
+++ b/interface/wx/ffile.h
@@ -54,7 +54,7 @@ public:
         @warning
         You should use IsOpened() to verify that the constructor succeeded.
     */
-    wxTempFFile(const wxString& strName);
+    explicit wxTempFFile(const wxString& strName);
 
     /**
         Destructor calls Discard() if temporary file is still open.
diff --git a/interface/wx/file.h b/interface/wx/file.h
index adb0f3086b..6be40318e9 100644
--- a/interface/wx/file.h
+++ b/interface/wx/file.h
@@ -52,7 +52,7 @@ public:
         @warning
         You should use IsOpened() to verify that the constructor succeeded.
     */
-    wxTempFile(const wxString& strName);
+    explicit wxTempFile(const wxString& strName);
 
     /**
         Destructor calls Discard() if temporary file is still open.