Failed to add apt key via server keyserver.ubuntu.com: Error: Command failed with exit code 2: sudo 'gpg' '--no-default-keyring' '--keyring' 'gnupg-ring:/etc/apt/trusted.gpg.d/setup-cpp-ubuntu-archive.gpg' '--keyserver' 'keyserver.ubuntu.com' '--recv-keys' '40976EAF437D05B5'

comparison of integer expressions of different signedness: ‘std::__cxx11::basic_string<char>::size_type’ {aka ‘long unsigned int’} and ‘int’ [-Wsign-compare]

‘undef_srst’ may be used uninitialized [-Wmaybe-uninitialized]

‘undef_ce’ may be used uninitialized [-Wmaybe-uninitialized]

‘undef_srst’ may be used uninitialized [-Wmaybe-uninitialized]

‘void* realloc(void*, size_t)’ moving an object of non-trivially copyable type ‘class Minisat::vec<unsigned int>’; use ‘new’ and ‘delete’ instead [-Wclass-memaccess]

‘void* realloc(void*, size_t)’ moving an object of non-trivially copyable type ‘class Minisat::vec<Minisat::Solver::Watcher>’; use ‘new’ and ‘delete’ instead [-Wclass-memaccess]

comparison of integer expressions of different signedness: ‘std::__cxx11::basic_string<char>::size_type’ {aka ‘long unsigned int’} and ‘int’ [-Wsign-compare]

‘undef_srst’ may be used uninitialized [-Wmaybe-uninitialized]

‘undef_ce’ may be used uninitialized [-Wmaybe-uninitialized]

‘undef_srst’ may be used uninitialized [-Wmaybe-uninitialized]

‘void* realloc(void*, size_t)’ moving an object of non-trivially copyable type ‘class Minisat::vec<unsigned int>’; use ‘new’ and ‘delete’ instead [-Wclass-memaccess]