This means we don't need to add the new member to the explicit
instantiation definition.
libstdc++-v3/ChangeLog:
* include/std/istream (istream::ignore(streamsize, char)): Add
always_inline attribute.
libstdc++-v3/ChangeLog:
* include/std/istream (ignore): Add an overload for char.
* testsuite/27_io/basic_istream/ignore/char/93672.cc: Adjust
expected behaviour for C++26 mode.
* testsuite/27_io/basic_istream/ignore/char/4.cc: New test.
Co-authored-by: Jonathan Wakely <jwakely@redhat.com>
Some tests e.g. 17_intro/headers/c++1998/all_pedantic_errors.cc FAIL
with GLIBCXX_TESTSUITE_STDS=98 due to numerous C++11 extensions still in
use in the library headers. The recent changes to not make them system
headers means we get warnings now.
This change adds more diagnostic pragmas to suppress those warnings.
libstdc++-v3/ChangeLog:
* include/bits/istream.tcc: Add diagnostic pragmas around uses
of long long and extern template.
* include/bits/locale_facets.h: Likewise.
* include/bits/locale_facets.tcc: Likewise.
* include/bits/locale_facets_nonio.tcc: Likewise.
* include/bits/ostream.tcc: Likewise.
* include/bits/stl_algobase.h: Likewise.
* include/c_global/cstdlib: Likewise.
* include/ext/pb_ds/detail/resize_policy/hash_prime_size_policy_imp.hpp:
Likewise.
* include/ext/pointer.h: Likewise.
* include/ext/stdio_sync_filebuf.h: Likewise.
* include/std/istream: Likewise.
* include/std/ostream: Likewise.
* include/tr1/cmath: Likewise.
* include/tr1/type_traits: Likewise.
* include/tr1/functional_hash.h: Likewise. Remove semi-colons
at namespace scope that aren't needed after macro expansion.
* include/tr1/tuple: Remove semi-colon at namespace scope.
* include/bits/vector.tcc: Change LL suffix to just L.
-Wsign-compare complained about these comparisons between (unsigned) size_t
and (signed) streamsize, or between (unsigned) native_handle_type
and (signed) -1. Fixed by adding casts to unify the types.
libstdc++-v3/ChangeLog:
* include/std/istream: Add cast to avoid -Wsign-compare.
* include/std/stacktrace: Likewise.
This questionable combination of flags causes a number of errors. The
ones in the rvalue stream overloads need to be fixed in the gcc-14
branch so I'm committing it separately to simplify backporting.
libstdc++-v3/ChangeLog:
PR libstdc++/116070
* include/std/istream: Check feature test macro before using
is_class_v and is_same_v.
* include/std/ostream: Likewise.
We don't need any library concepts to define the constraints for rvalue
stream overloads, only compiler support. So change the test from using
__cpp_lib_concepts to __cpp_concepts >= 201907L.
libstdc++-v3/ChangeLog:
* include/std/istream (__rvalue_stream_extraction_t): Test
__cpp_concepts instead of __cpp_lib_concepts.
* include/std/ostream (__derived_from_ios_base): Likewise.
(__rvalue_stream_insertion_t): Likewise.
The following patch adds the easy part of <charconv>, <istream> and
<ostream> changes for extended floats.
In particular, for the first one only overloads where the _Float* has
the same format as float/double/long double and for the latter two
everything but the _GLIBCXX_HAVE_FLOAT128_MATH case.
For charconv, I'm not really familiar with it, I'm pretty sure
we need new libstdc++.so.6 side implementation of from_chars for
{,b}float16_t and for to_chars not really sure but for unspecified precision
if it should emit minimum characters that to_chars then can unambiguously
parse, I think it is less than in the float case. For float128_t
{to,from}_chars I think we even have it on the library side already, just
ifdefed for powerpc64le only.
For i/o stream operator<</>>, not sure what is better, if not providing
anything at all, or doing what we in the end do if user doesn't override
the virtual functions, or use {to,from}_chars under the hood, something
else?
Besides this, the patch adds some further missed
// { dg-options "-std=gnu++2b" }
spots, I've also noticed I got the formatting wrong in some testcases
by not using spaces around VERIFY conditions and elsewhere by having
space before ( for calls.
The testsuite coverage is limited, I've added test for from_chars because
it was easy to port, but not really sure what to do about to_chars, it has
for float/double huge testcases which would be excessive to repeat.
And for i/ostream not really sure what exactly is worth testing.
2022-11-01 Jakub Jelinek <jakub@redhat.com>
* include/std/charconv (from_chars, to_chars): Add _Float{32,64,128}
overloads for cases where those types match {float,double,long double}.
* include/std/istream (basic_istream::operator>>): Add
_Float{16,32,64,128} and __gnu_cxx::__bfloat16_t overloads.
* include/std/ostream (basic_ostream::operator<<): Add
_Float{16,32,64,128} and __gnu_cxx::__bfloat16_t overloads.
* testsuite/20_util/from_chars/8.cc: New test.
* testsuite/26_numerics/headers/cmath/nextafter_c++23.cc (test):
Formatting fixes.
* testsuite/26_numerics/headers/cmath/functions_std_c++23.cc: Add
dg-options "-std=gnu++2b".
(test_functions, main): Formatting fixes.
* testsuite/26_numerics/headers/cmath/c99_classification_macros_c++23.cc:
Add dg-options "-std=gnu++2b".
In r11-2581-g17abcc77341584 (for LWG 2499) I added overflow checks to
the pre-C++20 operator>>(istream&, char*) overload. Those checks can
cause extraction to stop after filling the buffer, where previously it
would have tried to extract another character and stopped at EOF. When
that happens we no longer set eofbit in the stream state, which is
consistent with the behaviour of the new C++20 overload, but is an
observable and unexpected change in the C++17 behaviour. What makes it
worse is that the behaviour change is dependent on optimization, because
__builtin_object_size is used to detect the buffer size and that only
works when optimizing.
To avoid the unexpected and optimization-dependent change in behaviour,
set eofbit manually if we stopped extracting because of the buffer size
check, but had reached EOF anyway. If the stream's rdstate() != goodbit
or width() is non-zero and smaller than the buffer, there's nothing to
do. Otherwise, we filled the buffer and need to check for EOF, and maybe
set eofbit.
The new check is guarded by #ifdef __OPTIMIZE__ because otherwise
__builtin_object_size is useless. There's no point compiling and
emitting dead code that can't be eliminated because we're not
optimizing.
We could add extra checks that the next character in the buffer is not
whitespace, to detect the case where we stopped early and prevented a
buffer overflow that would have happened otherwise. That would allow us
to assert or set badbit in the stream state when undefined behaviour was
prevented. However, those extra checks would increase the size of the
function, potentially reducing the likelihood of it being inlined, and
so making the buffer size detection less reliable. It seems preferable
to prevent UB and silently truncate, rather than miss the UB and allow
the overflow to happen.
libstdc++-v3/ChangeLog:
PR libstdc++/106248
* include/std/istream [C++17] (operator>>(istream&, char*)):
Set eofbit if we stopped extracting at EOF.
* testsuite/27_io/basic_istream/extractors_character/char/pr106248.cc:
New test.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/pr106248.cc:
New test.
The __rval_streamable() function was an attempt to test for
convertibility cheaply and without confusing diagnostics. It doesn't
work with Clang though, and is probably ill-formed.
Replace that helper function with a check for derivation from ios_base,
and use that in the alias templates __rvalue_stream_insertion_t and
__rvalue_stream_extraction_t. Use concepts for the constraints when
available.
libstdc++-v3/ChangeLog:
* include/std/istream (__rvalue_stream_extraction_t): Replace
use of __rval_streamable.
* include/std/ostream (__rvalue_stream_insertion_t): Likewise.
(__rval_streamable): Remove.
(_Require_derived_from_ios_base, __derived_from_ios_base): New
helper for checking constraints.
* testsuite/27_io/basic_istream/extractors_other/char/4.cc: Fix
reference to the wrong subclause of the standard.
* testsuite/27_io/basic_istream/extractors_other/wchar_t/4.cc:
Likewise.
* testsuite/27_io/basic_ostream/inserters_other/char/6.cc:
Likewise.
* testsuite/27_io/basic_ostream/inserters_other/wchar_t/6.cc:
Likewise.
* testsuite/27_io/basic_ostream/inserters_other/char/99692.cc:
New test.
* testsuite/27_io/filesystem/path/io/dr2989.cc: Adjust pruned
errors.
This implements the resolution of LWG 1203 so that the constraints for
rvalue stream insertion/extraction are simpler, and the return type is
the original rvalue stream type not its base class.
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
libstdc++-v3/ChangeLog:
* include/std/istream (operator>>(Istream&&, x&)): Simplify, as
per LWG 1203.
* include/std/ostream (operator<<(Ostream&&, const x&)):
Likewise.
* testsuite/27_io/basic_istream/extractors_character/char/lwg2499_neg.cc:
Adjust dg-error pattern.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499_neg.cc:
Likewise.
* testsuite/27_io/basic_istream/extractors_other/char/4.cc: Define
is_extractable trait to replace std::__is_extractable. Make it
work with rvalue streams as well as lvalues, to replace f() and
g() helper functions.
* testsuite/27_io/basic_istream/extractors_other/wchar_t/4.cc:
Likewise.
* testsuite/27_io/basic_ostream/inserters_other/char/6.cc:
Define is_insertable trait to replace std::__is_insertable. Make
it work with rvalue streams as well as lvalues, to replace f()
and g() helper functions.
* testsuite/27_io/basic_ostream/inserters_other/wchar_t/6.cc:
Likewise.
* testsuite/27_io/filesystem/path/io/dr2989.cc: Prune additional
errors from new constraints.
* testsuite/27_io/rvalue_streams-2.cc: Remove PR 80675 checks,
which are no longer expected to compile.
* testsuite/27_io/rvalue_streams.cc: Adjust existing test.
Verify LWG 1203 changes.
This adjusts the overflow prevention added to operator>> so that we can
distinguish "unknown size" from "zero size", and avoid writing anything
at all in to zero sized buffers.
This also removes the incorrect comment saying extraction stops at a
null byte.
libstdc++-v3/ChangeLog:
* include/std/istream (operator>>(istream&, char*)): Add
attributes to get warnings for pointers that are null or known
to point to the end of a buffer. Request upper bound from
__builtin_object_size check and handle zero-sized buffer case.
(operator>>(istream&, signed char))
(operator>>(istream&, unsigned char*)): Add attributes.
* testsuite/27_io/basic_istream/extractors_character/char/overflow.cc:
Check extracting into the middle of a buffer.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/overflow.cc: New test.
P0487R1 resolved LWG 2499 for C++20 by removing the operator>> overloads
that have high risk of buffer overflows. They were replaced by
equivalents that only accept a reference to an array, and so can
guarantee not to write past the end of the array.
In order to support both the old and new functionality, this patch
introduces a new overloaded __istream_extract function which takes a
maximum length. The new operator>> overloads use the array size as the
maximum length. The old overloads now use __builtin_object_size to
determine the available buffer size if available (which requires -O2) or
use numeric_limits<streamsize>::max()/sizeof(char_type) otherwise. This
is a change in behaviour, as the old overloads previously always used
numeric_limits<streamsize>::max(), without considering sizeof(char_type)
and without attempting to prevent overflows.
Because they now do little more than call __istream_extract, the old
operator>> overloads are very small inline functions. This means there
is no advantage to explicitly instantiating them in the library (in fact
that would prevent the __builtin_object_size checks from ever working).
As a result, the explicit instantiation declarations can be removed from
the header. The explicit instantiation definitions are still needed, for
backwards compatibility with existing code that expects to link to the
definitions in the library.
While working on this change I noticed that src/c++11/istream-inst.cc
has the following explicit instantiation definition:
template istream& operator>>(istream&, char*);
This had no effect (and so should not have been present in that file),
because there was an explicit specialization declared in <istream> and
defined in src/++98/istream.cc. However, this change removes the
explicit specialization, and now the explicit instantiation definition
is necessary to ensure the symbol gets defined in the library.
libstdc++-v3/ChangeLog:
* config/abi/pre/gnu.ver (GLIBCXX_3.4.29): Export new symbols.
* include/bits/istream.tcc (__istream_extract): New function
template implementing both of operator>>(istream&, char*) and
operator>>(istream&, char(&)[N]). Add explicit instantiation
declaration for it. Remove explicit instantiation declarations
for old function templates.
* include/std/istream (__istream_extract): Declare.
(operator>>(basic_istream<C,T>&, C*)): Define inline and simply
call __istream_extract.
(operator>>(basic_istream<char,T>&, signed char*)): Likewise.
(operator>>(basic_istream<char,T>&, unsigned char*)): Likewise.
(operator>>(basic_istream<C,T>&, C(7)[N])): Define for LWG 2499.
(operator>>(basic_istream<char,T>&, signed char(&)[N])):
Likewise.
(operator>>(basic_istream<char,T>&, unsigned char(&)[N])):
Likewise.
* include/std/streambuf (basic_streambuf): Declare char overload
of __istream_extract as a friend.
* src/c++11/istream-inst.cc: Add explicit instantiation
definition for wchar_t overload of __istream_extract. Remove
explicit instantiation definitions of old operator>> overloads
for versioned-namespace build.
* src/c++98/istream.cc (operator>>(istream&, char*)): Replace
with __istream_extract(istream&, char*, streamsize).
* testsuite/27_io/basic_istream/extractors_character/char/3.cc:
Do not use variable-length array.
* testsuite/27_io/basic_istream/extractors_character/char/4.cc:
Do not run test for C++20.
* testsuite/27_io/basic_istream/extractors_character/char/9555-ic.cc:
Do not test writing to pointers for C++20.
* testsuite/27_io/basic_istream/extractors_character/char/9826.cc:
Use array instead of pointer.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/3.cc:
Do not use variable-length array.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/4.cc:
Do not run test for C++20.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/9555-ic.cc:
Do not test writing to pointers for C++20.
* testsuite/27_io/basic_istream/extractors_character/char/lwg2499.cc:
New test.
* testsuite/27_io/basic_istream/extractors_character/char/lwg2499_neg.cc:
New test.
* testsuite/27_io/basic_istream/extractors_character/char/overflow.cc:
New test.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499.cc:
New test.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499_neg.cc:
New test.
* include/std/istream:
(__is_convertible_to_basic_istream_test(basic_istream<_Ch, _Up>*)): New.
(__do_is_convertible_to_basic_istream_impl): Likewise.
(__is_convertible_to_basic_istream_impl): Likewise.
(__is_convertible_to_basic_istream): Use the new base.
(__rvalue_istream_type): New.
(operator>>(_Istream&&, _Tp&&)): Use the new helper alias
for the SFINAE check, convert to the helper alias type before
doing the actual extraction.
* include/std/ostream:
(__is_convertible_to_basic_ostream_test(basic_ostream<_Ch, _Up>*)): New.
(__do_is_convertible_to_basic_ostream_impl): Likewise.
(__is_convertible_to_basic_ostream_impl): Likewise.
(__is_convertible_to_basic_ostream): Use the new base.
(__rvalue_ostream_type): New.
(operator<<(_Ostream&&, const _Tp&)): Use the new helper alias
for the SFINAE check, convert to the helper alias type before
doing the actual insertion.
* testsuite/27_io/rvalue_streams-2.cc: Add new tests.
From-SVN: r249468
The convertible_to traits need to use a variadic catch-all for the
false-cases.
* include/std/istream (__is_convertible_to_basic_istream):
Change the parameter of the false-case of __check to a variadic.
* include/std/ostream (__is_convertible_to_basic_ostream):
Likewise.
From-SVN: r243098
* include/std/istream (__is_convertible_to_basic_istream):
Change the return types of __check, introduce istream_type.
(operator>>(_Istream&&, _Tp&&)):
Use __is_convertible_to_basic_istream::istream_type as the return type.
* include/std/ostream (__is_convertible_to_basic_ostream):
Change the return types of __check, introduce ostream_type.
(operator>>(_Ostream&&, _Tp&&)):
Use __is_convertible_to_basic_ostream::ostream_type as the return type.
From-SVN: r243036
2010-11-18 Benjamin Kosnik <bkoz@redhat.com>
* config/*/*: Use headername alias to associate private includes
to public includes.
* include/*/*: Same.
* scripts/run_doxygen: Update for doxygen 1.7.2.
* doc/doxygen/user.cfg.in: Same.
* doc/doxygen/TODO: Remove.
* testsuite/*/std_c++0x_neg.cc: Adjust line number.
From-SVN: r168046
Jakub Jelinek