call GetCache() from a global object ctor to ensure that it is done before any threads are created

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@55393 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/string.cpp

@@ -60,10 +60,25 @@ const size_t wxString::npos = (size_t) -1;
 
 #if wxUSE_STRING_POS_CACHE
 
+struct wxStrCacheInitializer
+{
+    wxStrCacheInitializer()
+    {
+        // calling this function triggers s_cache initialization in it, and
+        // from now on it becomes safe to call from multiple threads
+        wxString::GetCache();
+    }
+};
+
+static wxStrCacheInitializer gs_stringCacheInit;
+
 // gdb seems to be unable to display thread-local variables correctly, at least
 // not my 6.4.98 version under amd64, so provide this debugging helper to do it
 #ifdef __WXDEBUG__
 
+namespace
+{
+
 struct wxStrCacheDumper
 {
     static void ShowAll()
@@ -85,6 +100,8 @@ struct wxStrCacheDumper
     }
 };
 
+} // anonymous namespace
+
 void wxDumpStrCache() { wxStrCacheDumper::ShowAll(); }
 
 #endif // __WXDEBUG__