[PATCH] sso-string@gnu-versioned-namespace [PR83077]
François Dumont
frs.dumont@gmail.com
Mon Oct 9 17:38:40 GMT 2023
On 09/10/2023 16:42, Iain Sandoe wrote:
> Hi François,
>
>> On 7 Oct 2023, at 20:32, François Dumont <frs.dumont@gmail.com> wrote:
>>
>> I've been told that previous patch generated with 'git diff -b' was not applying properly so here is the same patch again with a simple 'git diff'.
> Thanks, that did fix it - There are some training whitespaces in the config files, but I suspect that they need to be there since those have values appended during the configuration.
You're talking about the ones coming from regenerated Makefile.in and
configure I guess. I prefer not to edit those, those trailing
whitespaces are already in.
>
> Anyway, with this + the coroutines and contract v2 (weak def) fix, plus a local patch to enable versioned namespace on Darwin, I get results comparable with the non-versioned case - but one more patchlet is needed on yours (to allow for targets using emultated TLS):
>
> diff --git a/libstdc++-v3/config/abi/pre/gnu-versioned-namespace.ver b/libstdc++-v3/config/abi/pre/gnu-versioned-namespace.ver
> index 9fab8bead15..b7167fc0c2f 100644
> --- a/libstdc++-v3/config/abi/pre/gnu-versioned-namespace.ver
> +++ b/libstdc++-v3/config/abi/pre/gnu-versioned-namespace.ver
> @@ -78,6 +78,7 @@ GLIBCXX_8.0 {
>
> # thread/mutex/condition_variable/future
> __once_proxy;
> + __emutls_v._ZNSt3__81?__once_call*;
I can add this one, sure, even if it could be part of a dedicated patch.
I'm surprised that we do not need the __once_callable emul symbol too,
it would be more consistent with the non-versioned mode.
I'm pretty sure there are a bunch of other symbols missing, but this
mode is seldomly tested...
>
> # std::__convert_to_v
> _ZNSt3__814__convert_to_v*;
>
>
> thanks
> Iain
>
>>
>> On 07/10/2023 14:25, François Dumont wrote:
>>> Hi
>>>
>>> Here is a rebased version of this patch.
>>>
>>> There are few test failures when running 'make check-c++' but nothing new.
>>>
>>> Still, there are 2 patches awaiting validation to fix some of them, PR c++/111524 to fix another bunch and I fear that we will have to live with the others.
>>>
>>> libstdc++: [_GLIBCXX_INLINE_VERSION] Use cxx11 abi [PR83077]
>>>
>>> Use cxx11 abi when activating versioned namespace mode. To do support
>>> a new configuration mode where !_GLIBCXX_USE_DUAL_ABI and _GLIBCXX_USE_CXX11_ABI.
>>>
>>> The main change is that std::__cow_string is now defined whenever _GLIBCXX_USE_DUAL_ABI
>>> or _GLIBCXX_USE_CXX11_ABI is true. Implementation is using available std::string in
>>> case of dual abi and a subset of it when it's not.
>>>
>>> On the other side std::__sso_string is defined only when _GLIBCXX_USE_DUAL_ABI is true
>>> and _GLIBCXX_USE_CXX11_ABI is false. Meaning that std::__sso_string is a typedef for the
>>> cow std::string implementation when dual abi is disabled and cow string is being used.
>>>
>>> libstdcxx-v3/ChangeLog:
>>>
>>> PR libstdc++/83077
>>> * acinclude.m4 [GLIBCXX_ENABLE_LIBSTDCXX_DUAL_ABI]: Default to "new" libstdcxx abi
>>> when enable_symvers is gnu-versioned-namespace.
>>> * config/locale/dragonfly/monetary_members.cc [!_GLIBCXX_USE_DUAL_ABI]: Define money_base
>>> members.
>>> * config/locale/generic/monetary_members.cc [!_GLIBCXX_USE_DUAL_ABI]: Likewise.
>>> * config/locale/gnu/monetary_members.cc [!_GLIBCXX_USE_DUAL_ABI]: Likewise.
>>> * config/locale/gnu/numeric_members.cc
>>> [!_GLIBCXX_USE_DUAL_ABI](__narrow_multibyte_chars): Define.
>>> * configure: Regenerate.
>>> * include/bits/c++config
>>> [_GLIBCXX_INLINE_VERSION](_GLIBCXX_NAMESPACE_CXX11, _GLIBCXX_BEGIN_NAMESPACE_CXX11):
>>> Define empty.
>>> [_GLIBCXX_INLINE_VERSION](_GLIBCXX_END_NAMESPACE_CXX11, _GLIBCXX_DEFAULT_ABI_TAG):
>>> Likewise.
>>> * include/bits/cow_string.h [!_GLIBCXX_USE_CXX11_ABI]: Define a light version of COW
>>> basic_string as __std_cow_string for use in stdexcept.
>>> * include/std/stdexcept [_GLIBCXX_USE_CXX11_ABI]: Define __cow_string.
>>> (__cow_string(const char*)): New.
>>> (__cow_string::c_str()): New.
>>> * python/libstdcxx/v6/printers.py (StdStringPrinter::__init__): Set self.new_string to True
>>> when std::__8::basic_string type is found.
>>> * src/Makefile.am [ENABLE_SYMVERS_GNU_NAMESPACE](ldbl_alt128_compat_sources): Define empty.
>>> * src/Makefile.in: Regenerate.
>>> * src/c++11/Makefile.am (cxx11_abi_sources): Rename into...
>>> (dual_abi_sources): ...this. Also move cow-local_init.cc, cxx11-hash_tr1.cc,
>>> cxx11-ios_failure.cc entries to...
>>> (sources): ...this.
>>> (extra_string_inst_sources): Move cow-fstream-inst.cc, cow-sstream-inst.cc, cow-string-inst.cc,
>>> cow-string-io-inst.cc, cow-wtring-inst.cc, cow-wstring-io-inst.cc, cxx11-locale-inst.cc,
>>> cxx11-wlocale-inst.cc entries to...
>>> (inst_sources): ...this.
>>> * src/c++11/Makefile.in: Regenerate.
>>> * src/c++11/cow-fstream-inst.cc [_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/cow-locale_init.cc [_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/cow-sstream-inst.cc [_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/cow-stdexcept.cc [_GLIBCXX_USE_CXX11_ABI]: Include <bits/cow_string.h>.
>>> [_GLIBCXX_USE_DUAL_ABI || _GLIBCXX_USE_CXX11_ABI](__cow_string): Redefine before
>>> including <stdexcept>. Define _GLIBCXX_DEFINE_STDEXCEPT_INSTANTIATIONS so that
>>> __cow_string definition in <stdexcept> is skipped.
>>> [_GLIBCXX_USE_CXX11_ABI]: Skip Transaction Memory TS definitions.
>>> * src/c++11/string-inst.cc: Add sizeof/alignof static_assert on stdexcept
>>> __cow_string definition.
>>> (_GLIBCXX_DEFINING_CXX11_ABI_INSTANTIATIONS): Define following _GLIBCXX_USE_CXX11_ABI
>>> value.
>>> [_GLIBCXX_USE_CXX11_ABI && !_GLIBCXX_DEFINING_CXX11_ABI_INSTANTIATIONS]:
>>> Define _GLIBCXX_DEFINING_COW_STRING_INSTANTIATIONS. Include <bits/cow_string.h>.
>>> Define basic_string as __std_cow_string for the current translation unit.
>>> * src/c++11/cow-string-inst.cc [_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/cow-string-io-inst.cc [_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/cow-wstring-inst.cc [_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/cow-wstring-io-inst.cc [_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/cxx11-hash_tr1.cc [!_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/cxx11-ios_failure.cc [!_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> [!_GLIBCXX_USE_DUAL_ABI] (__ios_failure): Remove.
>>> * src/c++11/cxx11-locale-inst.cc: Cleanup, just include locale-inst.cc.
>>> * src/c++11/cxx11-stdexcept.cc [!_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/cxx11-wlocale-inst.cc [!_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++11/locale-inst-numeric.h
>>> [!_GLIBCXX_USE_DUAL_ABI](std::use_facet<num_get<>>, std::use_facet<num_put<>>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](std::has_facet<num_get<>>, std::has_facet<num_put<>>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](std::num_get<C, istreambuf_iterator<C>>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](std::num_put<C, ostreambuf_iterator<C>>): Instantiate.
>>> * src/c++11/locale-inst.cc [!_GLIBCXX_USE_DUAL_ABI]: Build only when configured
>>> _GLIBCXX_USE_CXX11_ABI is equal to currently built abi.
>>> [!_GLIBCXX_USE_DUAL_ABI](__moneypunct_cache<C, false>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](__moneypunct_cache<C, true>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](__numpunct_cache<C>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](__timepunct<C>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](__timepunct_cache<C>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](time_put<C, ostreambuf_iterator<C>>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](time_put_byname<C, ostreambuf_iterator<C>>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](__ctype_abstract_base<C>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](ctype_byname<C>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](__codecvt_abstract_base<C, char, mbstate_t>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](codecvt_byname<C, char, mbstate_t>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](use_facet<ctype<C>>(const locale&)): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](use_facet<codecvt<C, char, mbstate_t>>(const locale&)): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](use_facet<__timepunct<C>>(const locale&)): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](use_facet<time_put<C>>(const locale&)): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](has_facet<ctype<C>>(const locale&)): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](has_facet<codecvt<C, char, mbstate_t>>(const locale&)): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](has_facet<__timepunct<C>>(const locale&)): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](has_facet<time_put<C>>(const locale&)): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](__add_grouping<C>): Define.
>>> [!_GLIBCXX_USE_DUAL_ABI](__pad<C, char_traits<C>>): Instantiate.
>>> [!_GLIBCXX_USE_DUAL_ABI](__int_to_char(C*, unsigned long, const C*,
>>> ios_base::fmtflags, bool)): Define.
>>> [!_GLIBCXX_USE_DUAL_ABI](__int_to_char(C*, unsigned long long, const C*,
>>> ios_base::fmtflags, bool)): Define.
>>> * src/c++11/wlocale-inst.cc [!_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++98/Makefile.am (cxx11_abi_sources): Remove, unique cow-istream-string.cc entry
>>> move to...
>>> (inst_sources): ...this.
>>> * src/c++98/Makefile.in: Regenerate.
>>> * src/c++98/cow-istream-string.cc: Include <bits/c++config.h>.
>>> [_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++98/hash_tr1.cc [_GLIBCXX_USE_CXX11_ABI]: Skip definitions.
>>> * src/c++98/ios_failure.cc [_GLIBCXX_USE_CXX11_ABI][_GLIBCXX_USE_DUAL_ABI]: Skip definitions.
>>> * src/c++98/istream-string.cc [!_GLIBCXX_USE_DUAL_ABI]: Build only when configured
>>> _GLIBCXX_USE_CXX11_ABI is equal to currently built abi.
>>> * src/c++98/locale_facets.cc [_GLIBCXX_USE_CXX11_ABI](__verify_grouping): Remove.
>>> * src/c++98/stdexcept.cc
>>> [_GLIBCXX_USE_CXX11_ABI](logic_error(const string&): Remove.
>>> [_GLIBCXX_USE_CXX11_ABI](domain_error(const string&): Remove.
>>> [_GLIBCXX_USE_CXX11_ABI](invalid_argument(const string&): Remove.
>>> [_GLIBCXX_USE_CXX11_ABI](length_error(const string&): Remove.
>>> [_GLIBCXX_USE_CXX11_ABI](out_of_range(const string&): Remove.
>>> [_GLIBCXX_USE_CXX11_ABI](runtime_error(const string&): Remove.
>>> [_GLIBCXX_USE_CXX11_ABI](range_error(const string&): Remove.
>>> [_GLIBCXX_USE_CXX11_ABI](overflow_error(const string&): Remove.
>>> [_GLIBCXX_USE_CXX11_ABI](underflow_error(const string&): Remove.
>>> * src/c++98/compatibility.cc [_GLIBCXX_USE_CXX11_ABI]: Skip all definitions appart from
>>> istream::ignore(streamsize).
>>>
>>> Tested under Linux x64_86, ok to commit ?
>>>
>>> François
>>>
>>>
>>> On 17/08/2023 19:22, Jonathan Wakely wrote:
>>>> On Sun, 13 Aug 2023 at 14:27, François Dumont via Libstdc++
>>>> <libstdc++@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.
>>>>
>>>>> 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.
>> <cxx11_gnu-versioned-ns.patch>
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