From 39380847da0b3989741667c53d9c251b58288b7b Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Wed, 20 Mar 2019 15:12:58 +0100
Subject: [PATCH] Avoid redundant declarations for wxQsort()

This works around gcc -Wredundant-decls warning that was given (if
explicitly enabled) when both wx/vector.h and wx/utils.h were included.

The workaround is ugly, but it doesn't seem worth it to introduce a
separate wx/qsort.h header just for this single function, which seems to
be the only other way to fix this.

Closes https://github.com/wxWidgets/wxWidgets/pull/1271
---
 include/wx/utils.h  | 7 +++++++
 include/wx/vector.h | 9 +++++++++
 2 files changed, 16 insertions(+)

diff --git a/include/wx/utils.h b/include/wx/utils.h
index 7cf8399f18..037bb88582 100644
--- a/include/wx/utils.h
+++ b/include/wx/utils.h
@@ -603,6 +603,11 @@ WXDLLIMPEXP_BASE bool wxGetDiskSpace(const wxString& path,
 
 
 
+// See wx/vector.h for more about this hack.
+#ifndef wxQSORT_DECLARED
+
+#define wxQSORT_DECLARED
+
 typedef int (*wxSortCallback)(const void* pItem1,
                               const void* pItem2,
                               const void* user_data);
@@ -612,6 +617,8 @@ WXDLLIMPEXP_BASE void wxQsort(void* pbase, size_t total_elems,
                               size_t size, wxSortCallback cmp,
                               const void* user_data);
 
+#endif // !wxQSORT_DECLARED
+
 
 #if wxUSE_GUI // GUI only things from now on
 
diff --git a/include/wx/vector.h b/include/wx/vector.h
index 25067081b4..c15d1630a6 100644
--- a/include/wx/vector.h
+++ b/include/wx/vector.h
@@ -41,6 +41,13 @@ inline void wxVectorSort(wxVector<T>& v)
 
 // wxQsort is declared in wx/utils.h, but can't include that file here,
 // it indirectly includes this file. Just lovely...
+//
+// Moreover, just declaring it here unconditionally results in gcc
+// -Wredundant-decls warning, so use a preprocessor guard to avoid this.
+#ifndef wxQSORT_DECLARED
+
+#define wxQSORT_DECLARED
+
 typedef int (*wxSortCallback)(const void* pItem1,
                               const void* pItem2,
                               const void* user_data);
@@ -48,6 +55,8 @@ WXDLLIMPEXP_BASE void wxQsort(void* pbase, size_t total_elems,
                               size_t size, wxSortCallback cmp,
                               const void* user_data);
 
+#endif // !wxQSORT_DECLARED
+
 namespace wxPrivate
 {