New installation leads to precompiled header compilation and fails

[maichmueller]

On a ubuntu 20.04 system with anaconda as package manager a basic installation (as per the docs) and subsequent import of cppyy in a python 3.9 shell will lead to the trigger of precompiling headers and fail.

System:

(cppyy) ➜  ~ uname -a
Linux MichaelDell 5.14.0-1057-oem #64-Ubuntu SMP Mon Jan 23 17:02:19 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

(cppyy) ➜  ~ gcc --version        
gcc (Anaconda gcc) 11.2.0
Copyright (C) 2021 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

(cppyy) ➜  ~ clang --version
Ubuntu clang version 12.0.0-3ubuntu1~20.04.5
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin

(cppyy) ➜  ~ python --version
Python 3.9.16

Steps to reproduce:

conda create -n cppyy python=3.9
conda activate cppyy
conda install -c conda-forge cppyy
python -c 'import cppyy'

Output generated:

(Re-)building pre-compiled headers (options: -O2 -march=native); this may take a minute ...
In file included from input_line_10:9:
In file included from ./etc/dictpch/allHeaders.h:50:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/ctime:80:11: error: no member named 'timespec_get' in the global namespace
  using ::timespec_get;
        ~~^
In file included from input_line_10:9:
In file included from ./etc/dictpch/allHeaders.h:116:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/cuchar:53:
/usr/include/uchar.h:36:9: error: unknown type name '__uint_least16_t'
typedef __uint_least16_t char16_t;
        ^
/usr/include/uchar.h:37:9: error: unknown type name '__uint_least32_t'
typedef __uint_least32_t char32_t;
        ^
Error: ./bin/rootcling: compilation failure (/tmp/allDict71623961b9_dictUmbrella.h)
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/loader.py:139: UserWarning: No precompiled header available (failed to build); this may impact performance.
  warnings.warn('No precompiled header available (%s); this may impact performance.' % msg)
In file included from libCoreLegacy dictionary payload:7:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Riostream.h:24:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/fstream:40:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/codecvt.h:344:20: error: explicit specialization of undeclared template class 'messages'
      friend class messages<char>;
                   ^       ~~~~~~
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/codecvt.h:407:20: error: explicit specialization of undeclared template class 'messages'
      friend class messages<wchar_t>;
                   ^       ~~~~~~~~~
In file included from input_line_3:1:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:28:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/atomic:41:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/atomic_base.h:38:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:57:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:149:41: error: no member named 'value' in 'std::__is_tuple_like<_IO_FILE *>'
    : public __bool_constant<!bool(_Pp::value)>
                                   ~~~~~^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:144:26: note: in instantiation of template class 'std::__not_<std::__is_tuple_like<_IO_FILE *> >' requested here
    : public conditional<_B1::value, __and_<_B2, _B3, _Bn...>, _B1>::type
                         ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:190:24: note: in instantiation of template class 'std::__and_<std::__not_<std::__is_tuple_like<_IO_FILE *> >, std::is_move_constructible<_IO_FILE *>, std::is_move_assignable<_IO_FILE *> >' requested here
    typename enable_if<__and_<__not_<__is_tuple_like<_Tp>>,
                       ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/x86_64-conda-linux-gnu/bits/basic_file.h:79:2: note: while substituting deduced template arguments into function template 'swap' [with _Tp = _IO_FILE *]
        std::swap(_M_cfile, __f._M_cfile);
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/x86_64-conda-linux-gnu/bits/basic_file.h:79:2: error: no matching function for call to 'swap'
        std::swap(_M_cfile, __f._M_cfile);
        ^~~~~~~~~
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_bvector.h:118:3: note: candidate function not viable: no known conversion from 'std::__c_file *' (aka '_IO_FILE *') to 'std::_Bit_reference' for 1st argument
  swap(_Bit_reference __x, _Bit_reference __y) noexcept
  ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_bvector.h:126:3: note: candidate function not viable: no known conversion from 'std::__c_file *' (aka '_IO_FILE *') to 'std::_Bit_reference' for 1st argument
  swap(_Bit_reference __x, bool& __y) noexcept
  ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_bvector.h:134:3: note: candidate function not viable: no known conversion from 'std::__c_file *' (aka '_IO_FILE *') to 'bool &' for 1st argument
  swap(bool& __x, _Bit_reference __y) noexcept
  ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:196:5: note: candidate template ignored: substitution failure [with _Tp = _IO_FILE *]
    swap(_Tp& __a, _Tp& __b)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:220:5: note: candidate template ignored: could not match '_Tp [_Nm]' against 'std::__c_file *' (aka '_IO_FILE *')
    swap(_Tp (&__a)[_Nm], _Tp (&__b)[_Nm])
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_pair.h:533:5: note: candidate template ignored: could not match 'pair<type-parameter-0-0, type-parameter-0-1>' against '_IO_FILE *'
    swap(pair<_T1, _T2>& __x, pair<_T1, _T2>& __y)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_pair.h:541:5: note: candidate template ignored: could not match 'pair<type-parameter-0-0, type-parameter-0-1>' against '_IO_FILE *'
    swap(pair<_T1, _T2>&, pair<_T1, _T2>&) = delete;
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:6492:5: note: candidate template ignored: could not match 'basic_string<type-parameter-0-0, type-parameter-0-1, type-parameter-0-2>' against '_IO_FILE *'
    swap(basic_string<_CharT, _Traits, _Alloc>& __lhs,
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_vector.h:1962:5: note: candidate template ignored: could not match 'vector<type-parameter-0-0, type-parameter-0-1>' against '_IO_FILE *'
    swap(vector<_Tp, _Alloc>& __x, vector<_Tp, _Alloc>& __y)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/array:348:5: note: candidate template ignored: could not match 'array<type-parameter-0-0, _Nm>' against '_IO_FILE *'
    swap(array<_Tp, _Nm>& __one, array<_Tp, _Nm>& __two)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/array:356:5: note: candidate template ignored: could not match 'array<type-parameter-0-0, _Nm>' against '_IO_FILE *'
    swap(array<_Tp, _Nm>&, array<_Tp, _Nm>&) = delete;
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/tuple:1749:5: note: candidate template ignored: could not match 'tuple<type-parameter-0-0...>' against '_IO_FILE *'
    swap(tuple<_Elements...>& __x, tuple<_Elements...>& __y)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/tuple:1757:5: note: candidate template ignored: could not match 'tuple<type-parameter-0-0...>' against '_IO_FILE *'
    swap(tuple<_Elements...>&, tuple<_Elements...>&) = delete;
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/std_function.h:728:5: note: candidate template ignored: could not match 'function<type-parameter-0-0 (type-parameter-0-1...)>' against '_IO_FILE *'
    swap(function<_Res(_Args...)>& __x, function<_Res(_Args...)>& __y) noexcept
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/unordered_map.h:2120:5: note: candidate template ignored: could not match 'unordered_map<type-parameter-0-0, type-parameter-0-1, type-parameter-0-2, type-parameter-0-3, type-parameter-0-4>' against '_IO_FILE *'
    swap(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/unordered_map.h:2127:5: note: candidate template ignored: could not match 'unordered_multimap<type-parameter-0-0, type-parameter-0-1, type-parameter-0-2, type-parameter-0-3, type-parameter-0-4>' against '_IO_FILE *'
    swap(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
    ^
In file included from input_line_3:1:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:28:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/atomic:41:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/atomic_base.h:38:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:57:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:149:41: error: no member named 'value' in 'std::__is_tuple_like<bool>'
    : public __bool_constant<!bool(_Pp::value)>
                                   ~~~~~^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:144:26: note: in instantiation of template class 'std::__not_<std::__is_tuple_like<bool> >' requested here
    : public conditional<_B1::value, __and_<_B2, _B3, _Bn...>, _B1>::type
                         ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:190:24: note: in instantiation of template class 'std::__and_<std::__not_<std::__is_tuple_like<bool> >, std::is_move_constructible<bool>, std::is_move_assignable<bool> >' requested here
    typename enable_if<__and_<__not_<__is_tuple_like<_Tp>>,
                       ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/x86_64-conda-linux-gnu/bits/basic_file.h:80:2: note: while substituting deduced template arguments into function template 'swap' [with _Tp = bool]
        std::swap(_M_cfile_created, __f._M_cfile_created);
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/x86_64-conda-linux-gnu/bits/basic_file.h:80:2: error: no matching function for call to 'swap'
        std::swap(_M_cfile_created, __f._M_cfile_created);
        ^~~~~~~~~
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_bvector.h:126:3: note: candidate function not viable: no known conversion from 'bool' to 'std::_Bit_reference' for 1st argument
  swap(_Bit_reference __x, bool& __y) noexcept
  ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_bvector.h:134:3: note: candidate function not viable: no known conversion from 'bool' to 'std::_Bit_reference' for 2nd argument
  swap(bool& __x, _Bit_reference __y) noexcept
  ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_bvector.h:118:3: note: candidate function not viable: no known conversion from 'bool' to 'std::_Bit_reference' for 1st argument
  swap(_Bit_reference __x, _Bit_reference __y) noexcept
  ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:196:5: note: candidate template ignored: substitution failure [with _Tp = bool]
    swap(_Tp& __a, _Tp& __b)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:220:5: note: candidate template ignored: could not match '_Tp [_Nm]' against 'bool'
    swap(_Tp (&__a)[_Nm], _Tp (&__b)[_Nm])
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_pair.h:533:5: note: candidate template ignored: could not match 'pair<type-parameter-0-0, type-parameter-0-1>' against 'bool'
    swap(pair<_T1, _T2>& __x, pair<_T1, _T2>& __y)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_pair.h:541:5: note: candidate template ignored: could not match 'pair<type-parameter-0-0, type-parameter-0-1>' against 'bool'
    swap(pair<_T1, _T2>&, pair<_T1, _T2>&) = delete;
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:6492:5: note: candidate template ignored: could not match 'basic_string<type-parameter-0-0, type-parameter-0-1, type-parameter-0-2>' against 'bool'
    swap(basic_string<_CharT, _Traits, _Alloc>& __lhs,
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/stl_vector.h:1962:5: note: candidate template ignored: could not match 'vector<type-parameter-0-0, type-parameter-0-1>' against 'bool'
    swap(vector<_Tp, _Alloc>& __x, vector<_Tp, _Alloc>& __y)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/array:348:5: note: candidate template ignored: could not match 'array<type-parameter-0-0, _Nm>' against 'bool'
    swap(array<_Tp, _Nm>& __one, array<_Tp, _Nm>& __two)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/array:356:5: note: candidate template ignored: could not match 'array<type-parameter-0-0, _Nm>' against 'bool'
    swap(array<_Tp, _Nm>&, array<_Tp, _Nm>&) = delete;
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/tuple:1749:5: note: candidate template ignored: could not match 'tuple<type-parameter-0-0...>' against 'bool'
    swap(tuple<_Elements...>& __x, tuple<_Elements...>& __y)
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/tuple:1757:5: note: candidate template ignored: could not match 'tuple<type-parameter-0-0...>' against 'bool'
    swap(tuple<_Elements...>&, tuple<_Elements...>&) = delete;
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/std_function.h:728:5: note: candidate template ignored: could not match 'function<type-parameter-0-0 (type-parameter-0-1...)>' against 'bool'
    swap(function<_Res(_Args...)>& __x, function<_Res(_Args...)>& __y) noexcept
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/unordered_map.h:2120:5: note: candidate template ignored: could not match 'unordered_map<type-parameter-0-0, type-parameter-0-1, type-parameter-0-2, type-parameter-0-3, type-parameter-0-4>' against 'bool'
    swap(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/unordered_map.h:2127:5: note: candidate template ignored: could not match 'unordered_multimap<type-parameter-0-0, type-parameter-0-1, type-parameter-0-2, type-parameter-0-3, type-parameter-0-4>' against 'bool'
    swap(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
    ^
In file included from input_line_3:1:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:28:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/atomic:41:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/atomic_base.h:38:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:57:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:1043:58: error: no member named 'value' in 'std::__is_referenceable<__mbstate_t, void>'
  template<typename _Tp, bool = __is_referenceable<_Tp>::value>
                                ~~~~~~~~~~~~~~~~~~~~~~~~~^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:1058:14: note: in instantiation of default argument for '__is_copy_assignable_impl<__mbstate_t>' required here
    : public __is_copy_assignable_impl<_Tp>::type
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:144:26: note: in instantiation of template class 'std::is_copy_assignable<__mbstate_t>' requested here
    : public conditional<_B1::value, __and_<_B2, _B3, _Bn...>, _B1>::type
                         ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/fstream:93:21: note: in instantiation of template class 'std::__and_<std::is_copy_assignable<__mbstate_t>, std::is_copy_constructible<__mbstate_t>, std::is_default_constructible<__mbstate_t> >' requested here
      static_assert(__chk_state<typename _Traits::state_type>::value,
                    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/fstream.tcc:1086:25: note: in instantiation of template class 'std::basic_filebuf<char, std::char_traits<char> >' requested here
  extern template class basic_filebuf<char>;
                        ^
In file included from input_line_3:1:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:28:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/atomic:41:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/atomic_base.h:38:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/move.h:57:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:116:31: error: no member named 'value' in 'std::is_lvalue_reference<__mbstate_t>'
    : public conditional<_B1::value, _B1, _B2>::type
                         ~~~~~^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:531:14: note: in instantiation of template class 'std::__or_<std::is_lvalue_reference<__mbstate_t>, std::is_rvalue_reference<__mbstate_t> >' requested here
    : public __or_<is_lvalue_reference<_Tp>,
             ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:121:26: note: in instantiation of template class 'std::is_reference<__mbstate_t>' requested here
    : public conditional<_B1::value, _B1, __or_<_B2, _B3, _Bn...>>::type
                         ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:206:24: note: in instantiation of template class 'std::__or_<std::is_reference<__mbstate_t>, std::is_function<__mbstate_t>, std::is_void<__mbstate_t>, std::__is_array_unknown_bounds<__mbstate_t> >' requested here
    constexpr typename __or_<
                       ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:1060:21: note: while substituting deduced template arguments into function template '__is_complete_or_unbounded' [with _TypeIdentity = std::__type_identity<__mbstate_t>, _NestedType = (no value)]
      static_assert(std::__is_complete_or_unbounded(__type_identity<_Tp>{}),
                    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/type_traits:144:26: note: in instantiation of template class 'std::is_copy_assignable<__mbstate_t>' requested here
    : public conditional<_B1::value, __and_<_B2, _B3, _Bn...>, _B1>::type
                         ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/fstream:93:21: note: in instantiation of template class 'std::__and_<std::is_copy_assignable<__mbstate_t>, std::is_copy_constructible<__mbstate_t>, std::is_default_constructible<__mbstate_t> >' requested here
      static_assert(__chk_state<typename _Traits::state_type>::value,
                    ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/fstream.tcc:1086:25: note: in instantiation of template class 'std::basic_filebuf<char, std::char_traits<char> >' requested here
  extern template class basic_filebuf<char>;
                        ^
In file included from libCoreLegacy dictionary payload:7:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Riostream.h:24:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/fstream:98:45: error: no member named 'value' in 'std::is_same<std::fpos<__mbstate_t>, std::fpos<__mbstate_t> >'
                            fpos<typename _Traits::state_type>>::value,
                            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/fstream.tcc:1086:25: note: in instantiation of template class 'std::basic_filebuf<char, std::char_traits<char> >' requested here
  extern template class basic_filebuf<char>;
                        ^
In file included from libCoreLegacy dictionary payload:7:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Riostream.h:24:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/fstream:93:64: error: no member named 'value' in 'std::__and_<std::is_copy_assignable<__mbstate_t>, std::is_copy_constructible<__mbstate_t>, std::is_default_constructible<__mbstate_t> >'
      static_assert(__chk_state<typename _Traits::state_type>::value,
                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/fstream.tcc:1092:25: note: in instantiation of template class 'std::basic_filebuf<wchar_t, std::char_traits<wchar_t> >' requested here
  extern template class basic_filebuf<wchar_t>;
                        ^
In file included from libCoreLegacy dictionary payload:7:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Riostream.h:24:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/fstream:98:45: error: no member named 'value' in 'std::is_same<std::fpos<__mbstate_t>, std::fpos<__mbstate_t> >'
                            fpos<typename _Traits::state_type>>::value,
                            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
In file included from libCoreLegacy dictionary payload:7:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Riostream.h:26:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/iomanip:43:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/locale:41:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/locale_facets_nonio.h:39:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/ctime:80:11: error: no member named 'timespec_get' in the global namespace
  using ::timespec_get;
        ~~^
In file included from libCoreLegacy dictionary payload:7:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Riostream.h:26:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/iomanip:43:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/locale:41:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/locale_facets_nonio.h:2031:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/locale_facets_nonio.tcc:160:9: error: no matching constructor for initialization of 'std::string' (aka 'basic_string<char>')
        string __grouping_tmp;
               ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:533:7: note: candidate constructor template not viable: requires at least argument '__s', but no arguments were provided
      basic_string(const _CharT* __s, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:553:7: note: candidate constructor template not viable: requires at least 2 arguments, but 0 were provided
      basic_string(size_type __n, _CharT __c, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:638:9: note: candidate constructor template not viable: requires at least 2 arguments, but 0 were provided
        basic_string(_InputIterator __beg, _InputIterator __end,
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:652:2: note: candidate constructor template not viable: requires at least 3 arguments, but 0 were provided
        basic_string(const _Tp& __t, size_type __pos, size_type __n,
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:663:2: note: candidate constructor template not viable: requires at least argument '__t', but no arguments were provided
        basic_string(const _Tp& __t, const _Alloc& __a = _Alloc())
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:448:7: note: candidate constructor not viable: requires single argument '__a', but no arguments were provided
      basic_string(const _Alloc& __a) _GLIBCXX_NOEXCEPT
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:456:7: note: candidate constructor not viable: requires single argument '__str', but no arguments were provided
      basic_string(const basic_string& __str)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:565:7: note: candidate constructor not viable: requires single argument '__str', but no arguments were provided
      basic_string(basic_string&& __str) noexcept
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:153:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(__sv_wrapper __svw, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:592:7: note: candidate constructor not viable: requires at least argument '__l', but no arguments were provided
      basic_string(initializer_list<_CharT> __l, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:596:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(const basic_string& __str, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:600:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(basic_string&& __str, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:469:7: note: candidate constructor not viable: requires at least 2 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:484:7: note: candidate constructor not viable: requires 3 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:518:7: note: candidate constructor not viable: requires at least 2 arguments, but 0 were provided
      basic_string(const _CharT* __s, size_type __n,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:500:7: note: candidate constructor not viable: requires 4 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
In file included from libCoreLegacy dictionary payload:7:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Riostream.h:26:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/iomanip:43:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/locale:41:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/locale_facets_nonio.h:2031:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/locale_facets_nonio.tcc:173:9: error: no matching constructor for initialization of 'std::string' (aka 'basic_string<char>')
        string __res;
               ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:533:7: note: candidate constructor template not viable: requires at least argument '__s', but no arguments were provided
      basic_string(const _CharT* __s, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:553:7: note: candidate constructor template not viable: requires at least 2 arguments, but 0 were provided
      basic_string(size_type __n, _CharT __c, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:638:9: note: candidate constructor template not viable: requires at least 2 arguments, but 0 were provided
        basic_string(_InputIterator __beg, _InputIterator __end,
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:652:2: note: candidate constructor template not viable: requires at least 3 arguments, but 0 were provided
        basic_string(const _Tp& __t, size_type __pos, size_type __n,
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:663:2: note: candidate constructor template not viable: requires at least argument '__t', but no arguments were provided
        basic_string(const _Tp& __t, const _Alloc& __a = _Alloc())
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:448:7: note: candidate constructor not viable: requires single argument '__a', but no arguments were provided
      basic_string(const _Alloc& __a) _GLIBCXX_NOEXCEPT
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:456:7: note: candidate constructor not viable: requires single argument '__str', but no arguments were provided
      basic_string(const basic_string& __str)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:565:7: note: candidate constructor not viable: requires single argument '__str', but no arguments were provided
      basic_string(basic_string&& __str) noexcept
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:153:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(__sv_wrapper __svw, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:592:7: note: candidate constructor not viable: requires at least argument '__l', but no arguments were provided
      basic_string(initializer_list<_CharT> __l, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:596:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(const basic_string& __str, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:600:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(basic_string&& __str, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:469:7: note: candidate constructor not viable: requires at least 2 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:484:7: note: candidate constructor not viable: requires 3 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:518:7: note: candidate constructor not viable: requires at least 2 arguments, but 0 were provided
      basic_string(const _CharT* __s, size_type __n,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:500:7: note: candidate constructor not viable: requires 4 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
In file included from libCoreLegacy dictionary payload:7:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Riostream.h:26:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/iomanip:43:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/locale:41:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/locale_facets_nonio.h:2031:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/locale_facets_nonio.tcc:374:14: error: no matching constructor for initialization of 'std::string' (aka 'basic_string<char>')
      string __str;
             ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:533:7: note: candidate constructor template not viable: requires at least argument '__s', but no arguments were provided
      basic_string(const _CharT* __s, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:553:7: note: candidate constructor template not viable: requires at least 2 arguments, but 0 were provided
      basic_string(size_type __n, _CharT __c, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:638:9: note: candidate constructor template not viable: requires at least 2 arguments, but 0 were provided
        basic_string(_InputIterator __beg, _InputIterator __end,
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:652:2: note: candidate constructor template not viable: requires at least 3 arguments, but 0 were provided
        basic_string(const _Tp& __t, size_type __pos, size_type __n,
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:663:2: note: candidate constructor template not viable: requires at least argument '__t', but no arguments were provided
        basic_string(const _Tp& __t, const _Alloc& __a = _Alloc())
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:448:7: note: candidate constructor not viable: requires single argument '__a', but no arguments were provided
      basic_string(const _Alloc& __a) _GLIBCXX_NOEXCEPT
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:456:7: note: candidate constructor not viable: requires single argument '__str', but no arguments were provided
      basic_string(const basic_string& __str)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:565:7: note: candidate constructor not viable: requires single argument '__str', but no arguments were provided
      basic_string(basic_string&& __str) noexcept
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:153:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(__sv_wrapper __svw, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:592:7: note: candidate constructor not viable: requires at least argument '__l', but no arguments were provided
      basic_string(initializer_list<_CharT> __l, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:596:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(const basic_string& __str, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:600:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(basic_string&& __str, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:469:7: note: candidate constructor not viable: requires at least 2 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:484:7: note: candidate constructor not viable: requires 3 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:518:7: note: candidate constructor not viable: requires at least 2 arguments, but 0 were provided
      basic_string(const _CharT* __s, size_type __n,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:500:7: note: candidate constructor not viable: requires 4 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
In file included from libCoreLegacy dictionary payload:7:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Riostream.h:26:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/iomanip:43:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/locale:41:
In file included from /home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/locale_facets_nonio.h:2031:
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/locale_facets_nonio.tcc:392:14: error: no matching constructor for initialization of 'std::string' (aka 'basic_string<char>')
      string __str;
             ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:533:7: note: candidate constructor template not viable: requires at least argument '__s', but no arguments were provided
      basic_string(const _CharT* __s, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:553:7: note: candidate constructor template not viable: requires at least 2 arguments, but 0 were provided
      basic_string(size_type __n, _CharT __c, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:638:9: note: candidate constructor template not viable: requires at least 2 arguments, but 0 were provided
        basic_string(_InputIterator __beg, _InputIterator __end,
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:652:2: note: candidate constructor template not viable: requires at least 3 arguments, but 0 were provided
        basic_string(const _Tp& __t, size_type __pos, size_type __n,
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:663:2: note: candidate constructor template not viable: requires at least argument '__t', but no arguments were provided
        basic_string(const _Tp& __t, const _Alloc& __a = _Alloc())
        ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:448:7: note: candidate constructor not viable: requires single argument '__a', but no arguments were provided
      basic_string(const _Alloc& __a) _GLIBCXX_NOEXCEPT
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:456:7: note: candidate constructor not viable: requires single argument '__str', but no arguments were provided
      basic_string(const basic_string& __str)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:565:7: note: candidate constructor not viable: requires single argument '__str', but no arguments were provided
      basic_string(basic_string&& __str) noexcept
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:153:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(__sv_wrapper __svw, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:592:7: note: candidate constructor not viable: requires at least argument '__l', but no arguments were provided
      basic_string(initializer_list<_CharT> __l, const _Alloc& __a = _Alloc())
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:596:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(const basic_string& __str, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:600:7: note: candidate constructor not viable: requires 2 arguments, but 0 were provided
      basic_string(basic_string&& __str, const _Alloc& __a)
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:469:7: note: candidate constructor not viable: requires at least 2 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:484:7: note: candidate constructor not viable: requires 3 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:518:7: note: candidate constructor not viable: requires at least 2 arguments, but 0 were provided
      basic_string(const _CharT* __s, size_type __n,
      ^
/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/basic_string.h:500:7: note: candidate constructor not viable: requires 4 arguments, but 0 were provided
      basic_string(const basic_string& __str, size_type __pos,
      ^
In file included from libCoreLegacy dictionary payload:9:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/TApplication.h:27:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/TObject.h:17:
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/TStorage.h:85:4: error: no member named 'value' in 'std::is_integral<int>'
   ClassDef(TStorage,0)  //Storage manager class
   ^~~~~~~~~~~~~~~~~~~~
input_line_14:4:27: note: expanded from macro 'ClassDef'
#define ClassDef(name,id) \
                          ^
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:294:4: note: expanded from macro '\
_ClassDefOutline_'
   _ClassDefBase_(name,id, virtual_keyword, overrd)       \
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:265:50: note: expanded from macro '_ClassDefBase_'
   static_assert(std::is_integral<decltype(id)>::value, "ClassDef(Inline) macro: the specified class version number is not an integer.");                                                        \
                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
In file included from libCoreLegacy dictionary payload:9:
In file included from /home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/TApplication.h:27:
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/TObject.h:194:4: error: no member named 'value' in 'std::is_integral<int>'
   ClassDef(TObject,1)  //Basic ROOT object
   ^~~~~~~~~~~~~~~~~~~
input_line_14:4:27: note: expanded from macro 'ClassDef'
#define ClassDef(name,id) \
                          ^
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:294:4: note: expanded from macro '\
_ClassDefOutline_'
   _ClassDefBase_(name,id, virtual_keyword, overrd)       \
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:265:50: note: expanded from macro '_ClassDefBase_'
   static_assert(std::is_integral<decltype(id)>::value, "ClassDef(Inline) macro: the specified class version number is not an integer.");                                                        \
                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
In file included from libCoreLegacy dictionary payload:9:
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/TApplication.h:71:4: error: no member named 'value' in 'std::is_integral<int>'
   ClassDef(TApplication,0)  //GUI application singleton
   ^~~~~~~~~~~~~~~~~~~~~~~~
input_line_14:4:27: note: expanded from macro 'ClassDef'
#define ClassDef(name,id) \
                          ^
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:294:4: note: expanded from macro '\
_ClassDefOutline_'
   _ClassDefBase_(name,id, virtual_keyword, overrd)       \
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/Rtypes.h:265:50: note: expanded from macro '_ClassDefBase_'
   static_assert(std::is_integral<decltype(id)>::value, "ClassDef(Inline) macro: the specified class version number is not an integer.");                                                        \
                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
fatal error: too many errors emitted, stopping now [-ferror-limit=]
 *** Break *** segmentation violation
 *** Break *** segmentation violation

[wlav]

I can't reproduce it, but it's clear that there's a mix-up of headers from the conda install and the system, where several public system C headers pick up internal implementation headers from conda. Reading the headers in more detail, that per se shouldn't be a problem, as all the above are protected with feature macro's, so maybe it goes wrong from the beginning first when the incorrect c++config.h (the system one) is being loaded.

What does strace python -c 'import cppyy' |& grep config.h show?

[maichmueller]

@wlav the output of the strace reads

(cppyy) ➜  ~ strace python -c 'import cppyy' |& grep config.h
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/bits/c++config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/x86_64-conda-linux-gnu/bits/c++config.h", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/pstl/pstl_config.h", O_RDONLY|O_CLOEXEC) = 3
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/etc/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/etc//cling/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/include/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/include/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/x86_64-conda-linux-gnu/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/c++/11.2.0/backward/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/lib/python3.9/site-packages/cppyy_backend/etc//cling/lib/clang/9.0.1/include/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/include/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/include-fixed/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../lib/gcc/x86_64-conda-linux-gnu/11.2.0/../../../../x86_64-conda-linux-gnu/include/_G_config.h", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/home/michael/anaconda3/envs/cppyy/bin/../x86_64-conda-linux-gnu/sysroot/usr/include/_G_config.h", O_RDONLY|O_CLOEXEC) = 3

[wlav]

That all looks correct ... I have no idea how this can then fail. :/

[wlav]

I still don't know how the above can fail, but cppyy 3.0.0 was released yesterday and is based on Clang13 (previous 2.4.2 was based on Clang9). If there were compatibility problems between that older Clang and specific versions of gcc, then these may have been fixed in Clang13 by upstream. It may be worth a try.

[maichmueller]

Since version 3.0 is not yet on the conda, I uninstalled it from the env and used pip to install version 3.0 instead. It seems that the new version is not installable either on my system with a different error message this time:

(cppyy) ➜  ~ pip install cppyy
Collecting cppyy
  Downloading cppyy-3.0.0.tar.gz (27 kB)
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
  Installing backend dependencies ... error
  error: subprocess-exited-with-error

  × pip subprocess to install backend dependencies did not run successfully.
  │ exit code: 1
  ╰─> [32 lines of output]
      Collecting cppyy-backend==1.14.11
        Downloading cppyy-backend-1.14.11.tar.gz (34 kB)
        Installing build dependencies: started
        Installing build dependencies: finished with status 'done'
        Getting requirements to build wheel: started
        Getting requirements to build wheel: finished with status 'done'
        Preparing metadata (pyproject.toml): started
        Preparing metadata (pyproject.toml): finished with status 'done'
      Collecting cppyy-cling==6.28.0
        Using cached cppyy_cling-6.28.0-py2.py3-none-manylinux2014_x86_64.whl (42.2 MB)
      Building wheels for collected packages: cppyy-backend
        Building wheel for cppyy-backend (pyproject.toml): started
        Building wheel for cppyy-backend (pyproject.toml): finished with status 'error'
        error: subprocess-exited-with-error

        × Building wheel for cppyy-backend (pyproject.toml) did not run successfully.
        │ exit code: 1
        ╰─> [8 lines of output]
            running bdist_wheel
            running build
            running build_ext
            checking for build/temp.linux-x86_64-cpython-39
            creating build/temp.linux-x86_64-cpython-39
            creating build/temp.linux-x86_64-cpython-39/src
            /home/michael/anaconda3/envs/cppyy/bin/x86_64-conda-linux-gnu-cc -Wno-unused-result -Wsign-compare -DNDEBUG -fwrapv -O2 -Wall -fPIC -O2 -isystem /home/michael/anaconda3/envs/cppyy/include -fPIC -O2 -isystem /home/michael/anaconda3/envs/cppyy/include -march=nocona -mtune=haswell -ftree-vectorize -fPIC -fstack-protector-strong -fno-plt -O2 -ffunction-sections -pipe -isystem /home/michael/anaconda3/envs/cppyy/include -DNDEBUG -D_FORTIFY_SOURCE=2 -O2 -isystem /home/michael/anaconda3/envs/cppyy/include -fPIC -I/tmp/pip-build-env-optws427/overlay/lib/python3.9/site-packages/cppyy_backend/include -I/home/michael/anaconda3/envs/cppyy/include/python3.9 -c src/clingwrapper.cxx -o build/temp.linux-x86_64-cpython-39/src/clingwrapper.o -O2 -pthread -std=c++1z -m64
            error: command '/home/michael/anaconda3/envs/cppyy/bin/x86_64-conda-linux-gnu-cc' failed: No such file or directory
            [end of output]

        note: This error originates from a subprocess, and is likely not a problem with pip.
        ERROR: Failed building wheel for cppyy-backend
      Failed to build cppyy-backend
      ERROR: Could not build wheels for cppyy-backend, which is required to install pyproject.toml-based projects
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
error: subprocess-exited-with-error

× pip subprocess to install backend dependencies did not run successfully.
│ exit code: 1
╰─> See above for output.

note: This error originates from a subprocess, and is likely not a problem with pip.

[maichmueller]

I just set up a fresh environment (as described before) and installed cppyy via pip. This now actually worked and i could import cppyy. Maybe the change for version 3.0 did fix the issue. I'm closing this for now then @wlav.

[wlav]

Thanks for letting me know; I still have no idea as to what went wrong in the first place.