https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91067
Viktor Ostashevskyi <ostash at ostash dot kiev.ua> changed:
What |Removed |Added
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CC| |ostash at ostash dot kiev.ua
--- Comment #10 from Viktor Ostashevskyi <ostash at ostash dot kiev.ua> ---
What about "base object constructors" (mangled with C2)?
For simple case like:
---
#include <filesystem>
#include <iostream>
int main(int argc, char** argv)
{
for (const auto& dirElem : std::filesystem::directory_iterator(argv[1]))
std::cout << dirElem.path().filename() << '\n';
}
---
When compiling with Clang 8 against libstdc++ from GCC 9.2.0 I got:
in function
`std::filesystem::directory_iterator::directory_iterator(std::filesystem::directory_iterator&&)':
fs.cpp:(.text._ZNSt10filesystem18directory_iteratorC2EOS0_[_ZNSt10filesystem18directory_iteratorC2EOS0_]+0x1):
undefined reference to `std::__shared_ptr<std::filesystem::_Dir,
(__gnu_cxx::_Lock_policy)2>::__shared_ptr(std::__shared_ptr<std::filesystem::_Dir,
(__gnu_cxx::_Lock_policy)2>&&)'
Checking in libstdc++.so showed that symbols are exported, but only for
complete object constructor:
_ZNSt12__shared_ptrINSt10filesystem7__cxx114_DirELN9__gnu_cxx12_Lock_policyE2EEC1EOS5_
Not sure why, but Clang emits call to base object constructor:
_ZNSt12__shared_ptrINSt10filesystem7__cxx114_DirELN9__gnu_cxx12_Lock_policyE2EEC2EOS5_
I've checked Clang8 vs libstdc++ from GCC 8.3.0 and see that it emits calls to
same base object ctor, but its definition is also emitted, so no linker error
occur.
