diff --git a/dlls/comdlg32/filedlg31.c b/dlls/comdlg32/filedlg31.c
index 89ef0e3e031..d74b1be7a54 100644
--- a/dlls/comdlg32/filedlg31.c
+++ b/dlls/comdlg32/filedlg31.c
@@ -738,7 +738,7 @@ static LPWSTR FD31_DupToW(LPCSTR str, DWORD size)
  *                              FD31_MapOfnStructA          [internal]
  *      map a 32 bits Ansi structure to a Unicode one
  */
-void FD31_MapOfnStructA(const OPENFILENAMEA *ofnA, LPOPENFILENAMEW ofnW, BOOL open)
+static void FD31_MapOfnStructA(const OPENFILENAMEA *ofnA, LPOPENFILENAMEW ofnW, BOOL open)
 {
     UNICODE_STRING usBuffer;
 
@@ -796,7 +796,7 @@ void FD31_MapOfnStructA(const OPENFILENAMEA *ofnA, LPOPENFILENAMEW ofnW, BOOL op
  *                              FD31_FreeOfnW          [internal]
  *      Undo all allocations done by FD31_MapOfnStructA
  */
-void FD31_FreeOfnW(OPENFILENAMEW *ofnW)
+static void FD31_FreeOfnW(OPENFILENAMEW *ofnW)
 {
    HeapFree(GetProcessHeap(), 0, (LPWSTR) ofnW->lpstrFilter);
    HeapFree(GetProcessHeap(), 0, ofnW->lpstrCustomFilter);
diff --git a/dlls/comdlg32/filedlg31.h b/dlls/comdlg32/filedlg31.h
index 79faed75e50..bb22005144e 100644
--- a/dlls/comdlg32/filedlg31.h
+++ b/dlls/comdlg32/filedlg31.h
@@ -40,8 +40,6 @@ extern BOOL FD32_GetTemplate(PFD31_DATA lfs);
 extern BOOL FD31_Init(void);
 extern PFD31_DATA FD31_AllocPrivate(LPARAM lParam, UINT dlgType, BOOL IsUnicode);
 extern void FD31_DestroyPrivate(PFD31_DATA lfs);
-extern void FD31_MapOfnStructA(const OPENFILENAMEA *ofnA, LPOPENFILENAMEW ofnW, BOOL open);
-extern void FD31_FreeOfnW(OPENFILENAMEW *ofnW);
 extern BOOL FD31_CallWindowProc(const FD31_DATA *lfs, UINT wMsg, WPARAM wParam,
                                 LPARAM lParam);
 extern LONG FD31_WMInitDialog(HWND hWnd, WPARAM wParam, LPARAM lParam);