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From: Iain Sandoe <iain@sandoe.co.uk>
To: Jonathan Wakely <jwakely@redhat.com>
Cc: "François Dumont" <frs.dumont@gmail.com>,
	"Jonathan Wakely" <jwakely.gcc@gmail.com>,
	libstdc++ <libstdc++@gcc.gnu.org>,
	"GCC Patches" <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH] sso-string@gnu-versioned-namespace [PR83077]
Date: Mon, 9 Oct 2023 17:27:14 +0100	[thread overview]
Message-ID: <0F6C3451-18B4-418A-A42F-63054BDA48CF@sandoe.co.uk> (raw)
In-Reply-To: <B7C82062-468B-4847-8C1B-8E543A4DE53B@googlemail.com>



> On 9 Oct 2023, at 15:42, Iain Sandoe <idsandoe@googlemail.com> wrote:

>> 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.
> 
> 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*;
> 
>     # std::__convert_to_v
>     _ZNSt3__814__convert_to_v*;

Having said this, since the versioned lib is an ABI-break, perhaps we should also take the opportunity
to fix the once_call impl. here too?

(at least the fix I made locally does not need the TLS var, so ths would then be moot)

Iain

> 
> 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>
> 


  reply	other threads:[~2023-10-09 16:27 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-08-10  5:13 François Dumont
2023-08-11  5:43 ` François Dumont
2023-08-11  7:51   ` Jonathan Wakely
2023-08-13 13:27     ` François Dumont
2023-08-13 19:51       ` François Dumont
2023-08-17 17:17         ` François Dumont
2023-08-24 17:33           ` François Dumont
2023-08-17 17:22       ` Jonathan Wakely
2023-08-17 17:40         ` François Dumont
2023-08-17 18:59           ` Jonathan Wakely
2023-08-17 19:37             ` Jonathan Wakely
2023-08-17 19:44               ` Jonathan Wakely
2023-08-17 23:31                 ` Jonathan Wakely
2023-08-19 19:44                 ` François Dumont
2023-10-07 12:25         ` François Dumont
2023-10-07 19:32           ` François Dumont
2023-10-09 14:42             ` Iain Sandoe
2023-10-09 16:27               ` Iain Sandoe [this message]
2023-10-09 17:38               ` François Dumont
2023-10-24  4:55             ` François Dumont
2024-02-28 18:37         ` François Dumont

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