From c7efab6d8a2a18ecea8d7b016915b94697a03165 Mon Sep 17 00:00:00 2001
From: Maarten Bent <MaartenBent@users.noreply.github.com>
Date: Sun, 17 Feb 2019 19:49:34 +0100
Subject: [PATCH] Fix using invalid HFONT in wxGetTextMetrics()

If the window has no valid font, GetFont() returns a temporary font.
Extend this font lifetime, so the HFONT remains valid till the end of
the function.
---
 src/msw/window.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/msw/window.cpp b/src/msw/window.cpp
index 5f8ef7791d..58d88811d2 100644
--- a/src/msw/window.cpp
+++ b/src/msw/window.cpp
@@ -7421,7 +7421,12 @@ static TEXTMETRIC wxGetTextMetrics(const wxWindowMSW *win)
 
 #if !wxDIALOG_UNIT_COMPATIBILITY
     // and select the current font into it
-    HFONT hfont = GetHfontOf(win->GetFont());
+
+    // Note that it's important to extend the lifetime of the possibly
+    // temporary wxFont returned by GetFont() to ensure that its HFONT remains
+    // valid.
+    const wxFont& f(win->GetFont());
+    HFONT hfont = GetHfontOf(f);
     if ( hfont )
     {
         hfont = (HFONT)::SelectObject(hdc, hfont);