TClassEdit name normalisation fails for unordered_map, leading to a crash in df104_CSVDataSource

[hageboeck]

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Description

The Python version of df104_CSV frequently crashes on Ubuntu when Cppyy queries types for unordered_map<string,char>. Although a TClass for this might exist, a query for

std::unordered_map<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, char, std::hash<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::equal_to<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, char> > >

might not normalise to the same class, so another TClass instance is created. During its creation, it deletes the instance for unordered_map<string,char>, leading to a dangling pointer and a use-after-free crash.

Reproducer

   auto first = TClass::GetClass("unordered_map<string,char>", true, true);
   std::unordered_map<std::string, char> map;
   auto second = first->GetActualClass(&map);
   EXPECT_EQ(first, second);

ROOT version

Master and v6.36

Installation method

Source

Operating system

All, but the crash manifests on Ubuntu

Additional context

No response