On Thu, 17 Aug 2023 at 20:37, Jonathan Wakely <jwak...@redhat.com> wrote: > > On Thu, 17 Aug 2023 at 19:59, Jonathan Wakely <jwak...@redhat.com> wrote: > > > > On Thu, 17 Aug 2023 at 18:40, François Dumont <frs.dum...@gmail.com> wrote: > > > > > > > > > On 17/08/2023 19:22, Jonathan Wakely wrote: > > > > On Sun, 13 Aug 2023 at 14:27, François Dumont via Libstdc++ > > > > <libstd...@gcc.gnu.org> wrote: > > > >> Here is the fixed patch tested in all 3 modes: > > > >> > > > >> - _GLIBCXX_USE_DUAL_ABI > > > >> > > > >> - !_GLIBCXX_USE_DUAL_ABI && !_GLIBCXX_USE_CXX11_ABI > > > >> > > > >> - !_GLIBCXX_USE_DUAL_ABI && _GLIBCXX_USE_CXX11_ABI > > > >> > > > >> I don't know what you have in mind for the change below but I wanted to > > > >> let you know that I tried to put COW std::basic_string into a nested > > > >> __cow namespace when _GLIBCXX_USE_CXX11_ABI. But it had more impact on > > > >> string-inst.cc so I preferred the macro substitution approach. > > > > I was thinking of implementing the necessary special members functions > > > > of __cow_string directly, so they are ABI compatible with the COW > > > > std::basic_string but don't actually reuse the code. That would mean > > > > we don't need to compile and instantiate the whole COW string just to > > > > use a few members from it. But that can be done later, the macro > > > > approach seems OK for now. > > > > > > You'll see that when cow_string.h is included while > > > _GLIBCXX_USE_CXX11_ABI == 1 then I am hiding a big part of the > > > basic_string definition. Initially it was to avoid to have to include > > > basic_string.tcc but it is also a lot of useless code indeed. > > > > > > > > > > > > > >> There are some test failing when !_GLIBCXX_USE_CXX11_ABI that are > > > >> unrelated with my changes. I'll propose fixes in coming days. > > > > Which tests? I run the entire testsuite with > > > > -D_GLIBCXX_USE_CXX11_ABI=0 several times per day and I'm not seeing > > > > failures. > > > > > > > > I'll review the patch ASAP, thanks for working on it. > > > > > > > So far the only issue I found are in the mode !_GLIBCXX_USE_DUAL_ABI && > > > !_GLIBCXX_USE_CXX11_ABI. They are: > > > > > > 23_containers/unordered_map/96088.cc > > > 23_containers/unordered_multimap/96088.cc > > > 23_containers/unordered_multiset/96088.cc > > > 23_containers/unordered_set/96088.cc > > > ext/debug_allocator/check_new.cc > > > ext/malloc_allocator/check_new.cc > > > ext/malloc_allocator/deallocate_local.cc > > > ext/new_allocator/deallocate_local.cc > > > ext/pool_allocator/allocate_chunk.cc > > > ext/throw_allocator/deallocate_local.cc > > > > Ah yes, they fail for !USE_DUAL_ABI builds, I wonder why. > > > > /home/test/src/gcc/libstdc++-v3/testsuite/23_containers/unordered_map/96088. > > cc:44: void test01(): Assertion '__gnu_test::counter::count() == 3' failed. > > FAIL: 23_containers/unordered_map/96088.cc execution test > > It's due to this global object in src/c++20/tzdb.cc: > 1081 const string tzdata_file = "/tzdata.zi"; > > When the library uses COW strings that requires an allocation before > main, which uses the replacement operator new in the tests, which > fails to allocate. For example, in 22_locale/locale/cons/12352.cc we > have this function used by operator new: > > int times_to_fail = 0; > > void* allocate(std::size_t n) > { > if (!times_to_fail--) > return 0; > > The counter is initially zero, so if we try to allocate before it gets > set to a non-zero value in test01() then we fail. > > The test should not assume no allocations before main() begins. The > simplest way to do that is with another global that says "we have > started testing" e.g. > > --- a/libstdc++-v3/testsuite/22_locale/locale/cons/12352.cc > +++ b/libstdc++-v3/testsuite/22_locale/locale/cons/12352.cc > @@ -26,11 +26,12 @@ > #include <cstring> > #include <testsuite_hooks.h> > > +bool tests_started = false; > int times_to_fail = 0; > > void* allocate(std::size_t n) > { > - if (!times_to_fail--) > + if (tests_started && !times_to_fail--) > return 0; > > void* ret = std::malloc(n ? n : 1); > @@ -106,6 +107,8 @@ void operator delete[](void* p, const > std::nothrow_t&) throw() > // libstdc++/12352 > void test01(int iters) > { > + tests_started = true; > + > for (int j = 0; j < iters; ++j) > { > for (int i = 0; i < 100; ++i) > > > This way the replacement operator new doesn't start intentionally > failing until we ask it to do so.
I'll replace the global std::string objects with std::string_view objects, so that they don't allocate even if the library only uses COW strings. We should still fix those tests though.