initialize a local variable even if it doesn't really need to be initialized to suppress annoying g++ warning in optimized build

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@54998 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/stringops.cpp

@@ -194,7 +194,7 @@ bool wxStringOperationsUtf8::IsValidUtf8LeadByte(unsigned char c)
 //     code in single place
 wxUniChar::Utf8CharBuffer wxUniChar::AsUTF8() const
 {
-    Utf8CharBuffer buf;
+    Utf8CharBuffer buf = { "" }; // init to avoid g++ 4.1 warning with -O2
     char *out = buf.data;
 
     value_type code = GetValue();