Fix Bug 25103 - _cxa_demangle improperly demangles virtual thunks. Thanks to Jason King for the report and suggested fix

llvm-svn: 250097

libcxxabi/src/cxa_demangle.cpp

@@ -4415,7 +4415,7 @@ parse_special_name(const char* first, const char* last, C& db)
                 {
                     if (db.names.empty())
                         return first;
-                    if (first[2] == 'v')
+                    if (first[1] == 'v')
                     {
                         db.names.back().first.insert(0, "virtual thunk to ");
                         first = t;

libcxxabi/test/test_demangle.pass.cpp

@@ -29594,6 +29594,8 @@ const char* cases[][2] =
     {"_Zli2_xy", "operator\"\" _x(unsigned long long)"},
     {"_Z1fIiEDcT_", "decltype(auto) f<int>(int)"},
     {"_ZZ4testvEN1g3fooE5Point", "test()::g::foo(Point)"},
+    {"_ZThn12_NSt9strstreamD0Ev",   "non-virtual thunk to std::strstream::~strstream()"},
+    {"_ZTv0_n12_NSt9strstreamD0Ev",     "virtual thunk to std::strstream::~strstream()"},
 };
 
 const unsigned N = sizeof(cases) / sizeof(cases[0]);