https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93469
Bug ID: 93469
Summary: memory header fails to compile with _XOPEN_SOURCE
macro defined and -std=c++2a option specified
Product: gcc
Version: 9.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: karen.arutyunov at gmail dot com
Target Milestone: ---
While packaging ICU 65.1 for build2 toolchain I end up with the following error
on macOS 10.15.2 with g++ 9.2.0 (Homebrew GCC 9.2.0_2):
In file included from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/bits/stl_algo.h:59,
from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/string:52,
from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/stdexcept:39,
from /usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/array:39,
from /usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/tuple:39,
from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/bits/unique_ptr.h:37,
from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/memory:80,
from
/Users/build/cfg/libicuuc-65.1.0-a.0.20200127171539.77d49624ec32/libicu/uc/unicode/localpointer.h:45,
from
/Users/build/cfg/libicuuc-65.1.0-a.0.20200127171539.77d49624ec32/libicu/uc/unicode/udata.h:23,
from
/Users/build/cfg/libicuuc-65.1.0-a.0.20200127171539.77d49624ec32/libicu/uc/udatamem.h:24,
from
/Users/build/cfg/libicuuc-65.1.0-a.0.20200127171539.77d49624ec32/libicu/uc/umapfile.cpp:26:
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/cstdlib:132:11: error:
'::aligned_alloc' has not been declared
132 | using ::aligned_alloc;
| ^~~~~~~~~~~~~
The issue seems to relate to libstdc++ headers and pops up if the C++20
standard is specified on the command line and a program defines the
_XOPEN_SOURCE macro and includes the memory header. It can be reproduced with
the following commands:
% cat <<EOF >test.cxx
#include <memory>
int main (int argc, char* argv[])
{
}
EOF
% g++-9 -D_XOPEN_SOURCE=500 test.cxx
% g++-9 -std=c++2a test.cxx
% g++-9 -D_XOPEN_SOURCE=500 -std=c++2a test.cxx
In file included from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/bits/stl_algo.h:59,
from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/string:52,
from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/stdexcept:39,
from /usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/array:39,
from /usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/tuple:39,
from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/bits/unique_ptr.h:37,
from
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/memory:80,
from test.cxx:1:
/usr/local/Cellar/gcc/9.2.0_2/include/c++/9.2.0/cstdlib:132:11: error:
'::aligned_alloc' has not been declared
132 | using ::aligned_alloc;
| ^~~~~~~~~~~~~
