When building with gcc 9.2.0, I get the following build error:
In file included from /home/simark/src/binutils-gdb/gdb/unittests/vec-utils-selftests.c:23:
/home/simark/src/binutils-gdb/gdb/gdbsupport/gdb_vecs.h: In instantiation of ‘T unordered_remove(std::__debug::vector<T>&, typename std::__debug::vector<T>::iterator) [with T = selftests::vector_utils_tests::unordered_remove_tests()::obj; typename std::__debug::vector<T>::iterator = __gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<selftests::vector_utils_tests::unordered_remove_tests()::obj*, std::__cxx1998::vector<selftests::vector_utils_tests::unordered_remove_tests()::obj, std::allocator<selftests::vector_utils_tests::unordered_remove_tests()::obj> > >, std::__debug::vector<selftests::vector_utils_tests::unordered_remove_tests()::obj>, std::random_access_iterator_tag>]’:
/home/simark/src/binutils-gdb/gdb/unittests/vec-utils-selftests.c:53:26: required from here
/home/simark/src/binutils-gdb/gdb/gdbsupport/gdb_vecs.h:53:5: error: implicitly-declared ‘selftests::vector_utils_tests::unordered_remove_tests()::obj::obj(const selftests::vector_utils_tests::unordered_remove_tests()::obj&)’ is deprecated [-Werror=deprecated-copy]
53 | T removed = std::move (*it);
| ^~~~~~~
/home/simark/src/binutils-gdb/gdb/unittests/vec-utils-selftests.c:41:10: note: because ‘selftests::vector_utils_tests::unordered_remove_tests()::obj’ has user-provided ‘selftests::vector_utils_tests::unordered_remove_tests()::obj& selftests::vector_utils_tests::unordered_remove_tests()::obj::operator=(const selftests::vector_utils_tests::unordered_remove_tests()::obj&)’
41 | obj &operator= (const obj &other)
| ^~~~~~~~
In file included from /home/simark/src/binutils-gdb/gdb/unittests/vec-utils-selftests.c:23:
/home/simark/src/binutils-gdb/gdb/gdbsupport/gdb_vecs.h:58:10: error: implicitly-declared ‘selftests::vector_utils_tests::unordered_remove_tests()::obj::obj(const selftests::vector_utils_tests::unordered_remove_tests()::obj&)’ is deprecated [-Werror=deprecated-copy]
58 | return removed;
| ^~~~~~~
/home/simark/src/binutils-gdb/gdb/unittests/vec-utils-selftests.c:41:10: note: because ‘selftests::vector_utils_tests::unordered_remove_tests()::obj’ has user-provided ‘selftests::vector_utils_tests::unordered_remove_tests()::obj& selftests::vector_utils_tests::unordered_remove_tests()::obj::operator=(const selftests::vector_utils_tests::unordered_remove_tests()::obj&)’
41 | obj &operator= (const obj &other)
| ^~~~~~~~
I think gcc is just trying to be nice and recommends the good practice
of providing a copy constructor if an assignment operator is provided.
Silence the warning by providing that copy constructor.
gdb/ChangeLog:
* unittests/vec-utils-selftests.c (unordered_remove_tests::obj):
Provide explicit default and copy constructor.
Change-Id: I323361b1c120bf8525613b74e7e5983910e002df
While working on another patch I ran into an issue with
unordered_remove (in gdb_vecs.h), where removing the last item of the
vector can cause a self move assign.
When compiling the C++ standard library in debug mode (with
-D_GLIBCXX_DEBUG=1) this causes an error to trigger.
I've fixed the issue in this patch and provided a unit test.
The provided unit test includes an assignment operator which checks
for self move assign, this removes the need to compile with
-D_GLIBCXX_DEBUG=1 in order to spot the bug. If you're keen to see
the error reported from the C++ standard library then remove operator=
from the unit test and recompile GDB with -D_GLIBCXX_DEBUG=1.
gdb/ChangeLog:
* Makefile.in (SUBDIR_UNITTESTS_SRCS): Add new file to the list.
* unittests/vec-utils-selftests.c: New file.
* gdbsupport/gdb_vecs.h (unordered_remove): Avoid self move assign.
Change-Id: I80247b20cd5212038117db7412865f5e6a9257cd