https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91067
Bug ID: 91067
Summary: Clang compiler can't link executable if
std::filesystem::directory_iterator is encountered
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: boris.staletic at gmail dot com
Target Milestone: ---
When compiling with clang, a code that contains an object of the type
std::filesystem::directory_iterator produces the following linker error:
/usr/sbin/ld: /tmp/bar-5627f7.o: in function
`std::filesystem::__cxx11::directory_iterator::directory_iterator()':
bar.cpp:(.text._ZNSt10filesystem7__cxx1118directory_iteratorC2Ev[_ZNSt10filesystem7__cxx1118directory_iteratorC2Ev]+0x1):
undefined reference to `std::__shared_ptr<std::filesystem::__cxx11::_Dir,
(__gnu_cxx::_Lock_policy)2>::__shared_ptr()'
clang-8: error: linker command failed with exit code 1 (use -v to see
invocation)
The minimal reproducer had to be preprocessed with clang to avoid errors like
"/usr/include/c++/9.1.0/bits/stl_function.h:475:6: error: use of undeclared
identifier '__builtin_is_constant_evaluated'" when compiling. For this reason I
will attach a non-preprocessed file too.
Clang version - 8.0.0 (tags/RELEASE_800/final)
Clang command line - clang++ -std=c++17 bar.ii -O1 -lstdc++fs
GCC version - 9.1.0
Target - x86_64-pc-linux-gnu
GCC compile time configuration options:
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/9.1.0/lto-wrapper
Configured with: /build/gcc/src/gcc/configure --prefix=/usr --libdir=/usr/lib
--libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info
--with-bugurl=https://bugs.archlinux.org/
--enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared
--enable-threads=posix --with-system-zlib --with-isl
--enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu
--disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object
--enable-linker-build-id --enable-lto --enable-plugin
--enable-install-libiberty --with-linker-hash-style=gnu
--enable-gnu-indirect-function --enable-multilib --disable-werror
--enable-checking=release --enable-default-pie --enable-default-ssp
--enable-cet=auto
Thread model: posix
Additional note: Changing the optimization level can avoid the linker error.
