Currently we only provide std::abs(__int128) and std::abs(__float128)
for non-strict modes, i.e. -std=gnu++NN but not -std=c++NN.
This defines those overloads for strict modes too, as a small step
towards resolving PR 96710 (which will eventually mean that __int128
satisfies the std::integral concept).
libstdc++-v3/ChangeLog:
PR libstdc++/96710
* include/bits/std_abs.h [__SIZEOF_INT128__] (abs(__int128)):
Define.
[_GLIBCXX_USE_FLOAT128] (abs(__float128)): Enable definition for
strict modes.
* testsuite/26_numerics/headers/cmath/82644.cc: Use strict_std
instead of defining __STRICT_ANSI__.
* testsuite/26_numerics/headers/cstdlib/abs128.cc: New test.
Reviewed-by: Tomasz Kamiński <tkaminsk@redhat.com>
The use of #pragma GCC system_header in libstdc++ has led to bugs going
undetected for a while due to the silencing of compiler warnings that would
have revealed them promptly, and also interferes with warnings about
problematic template instantiations induced by user code.
But removing it, or even compiling with -Wsystem-header, is also problematic
due to warnings about deliberate uses of extensions.
So this patch adds #pragma GCC diagnostic as needed to suppress these
warnings.
The change to acinclude.m4 changes -Wabi to warn only in comparison to ABI
19, to avoid lots of warnings that we now mangle concept requirements, which
are in any case still experimental. I checked for any other changes against
ABI v15, and found only the <format> lambda mangling, which we can ignore.
This also enables -Wsystem-headers while building the library, so we see any
warnings not silenced by these #pragmas.
libstdc++-v3/ChangeLog:
* include/bits/algorithmfwd.h:
* include/bits/allocator.h:
* include/bits/codecvt.h:
* include/bits/concept_check.h:
* include/bits/cpp_type_traits.h:
* include/bits/hashtable.h:
* include/bits/iterator_concepts.h:
* include/bits/ostream_insert.h:
* include/bits/ranges_base.h:
* include/bits/regex_automaton.h:
* include/bits/std_abs.h:
* include/bits/stl_algo.h:
* include/c_compatibility/fenv.h:
* include/c_compatibility/inttypes.h:
* include/c_compatibility/stdint.h:
* include/ext/concurrence.h:
* include/ext/type_traits.h:
* testsuite/ext/type_traits/add_unsigned_floating_neg.cc:
* testsuite/ext/type_traits/add_unsigned_integer_neg.cc:
* testsuite/ext/type_traits/remove_unsigned_floating_neg.cc:
* testsuite/ext/type_traits/remove_unsigned_integer_neg.cc:
* include/bits/basic_ios.tcc:
* include/bits/basic_string.tcc:
* include/bits/fstream.tcc:
* include/bits/istream.tcc:
* include/bits/locale_classes.tcc:
* include/bits/locale_facets.tcc:
* include/bits/ostream.tcc:
* include/bits/regex_compiler.tcc:
* include/bits/sstream.tcc:
* include/bits/streambuf.tcc:
* configure: Regenerate.
* include/bits/c++config:
* include/c/cassert:
* include/c/cctype:
* include/c/cerrno:
* include/c/cfloat:
* include/c/climits:
* include/c/clocale:
* include/c/cmath:
* include/c/csetjmp:
* include/c/csignal:
* include/c/cstdarg:
* include/c/cstddef:
* include/c/cstdio:
* include/c/cstdlib:
* include/c/cstring:
* include/c/ctime:
* include/c/cwchar:
* include/c/cwctype:
* include/c_global/climits:
* include/c_global/cmath:
* include/c_global/cstddef:
* include/c_global/cstdlib:
* include/decimal/decimal:
* include/ext/rope:
* include/std/any:
* include/std/charconv:
* include/std/complex:
* include/std/coroutine:
* include/std/format:
* include/std/iomanip:
* include/std/limits:
* include/std/numbers:
* include/tr1/functional:
* include/tr1/tuple:
* include/tr1/type_traits:
* libsupc++/compare:
* libsupc++/new: Add #pragma GCC diagnostic to suppress
undesired warnings.
* acinclude.m4: Change -Wabi version from 2 to 19.
gcc/ChangeLog:
* ginclude/stdint-wrap.h: Add #pragma GCC diagnostic to suppress
undesired warnings.
* gsyslimits.h: Likewise.
The current implementation of this non-standard overload of std::abs
incorrectly returns a negative value for negative NaNs and negative
zero, because x < 0 is false in both cases.
Use fabsl(long double) or fabsf128(_Float128) if those do the right
thing. Otherwise, use __builtin_signbit(x) instead of x < 0 to detect
negative inputs. This assumes that __builtin_signbit handles __float128
correctly, but that seems to be true for all of GCC, clang and icc.
libstdc++-v3/ChangeLog:
PR libstdc++/109758
* include/bits/std_abs.h (abs(__float128)): Handle negative NaN
and negative zero correctly.
* testsuite/26_numerics/headers/cmath/109758.cc: New test.
The following patch is partial support for std::float{16,32,64,128}_t
and std::bfloat16_t in libstdc++.
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p1467r9.html
says that <ostream>, <istream>, <charconv> and <complex>
need changes toom, but that isn't implemented so far.
In <cmath> the only thing missing I'm aware of is
std::nextafter std::float16_t and std::bfloat16_t overloads (I think
we probably need to implement that out of line somewhere, or inline? - might
need inline asm barriers) and std::nexttoward overloads (those are
intentional, you said there is a LWG issue about that).
Also, this patch has the glibc 2.26+ std::float128_t support for platforms
where long double isn't IEEE quad format temporarily disabled
because it depends on
https://gcc.gnu.org/pipermail/gcc-patches/2022-October/603665.html
changes which aren't in yet.
The patch also doesn't include any testcases to cover the <type_traits>
changes, it isn't clear to me where to put that.
2022-10-18 Jakub Jelinek <jakub@redhat.com>
PR c++/106652
* include/std/stdfloat: New file.
* include/std/numbers (__glibcxx_numbers): Define and use it
for __float128 explicit instantiations as well as
_Float{16,32,64,128} and __gnu_cxx::__bfloat16_t.
* include/std/atomic (atomic<_Float16>, atomic<_Float32>,
atomic<_Float64>, atomic<_Float128>, atomic<__gnu_cxx::__bfloat16_t>):
New explicit instantiations.
* include/std/type_traits (__is_floating_point_helper<_Float16>,
__is_floating_point_helper<_Float32>,
__is_floating_point_helper<_Float64>,
__is_floating_point_helper<_Float128>,
__is_floating_point_helper<__gnu_cxx::__bfloat16_t>): Likewise.
* include/std/limits (__glibcxx_concat3_, __glibcxx_concat3,
__glibcxx_float_n): Define.
(numeric_limits<_Float16>, numeric_limits<_Float32>,
numeric_limits<_Float64>, numeric_limits<_Float128>,
numeric_limits<__gnu_cxx::__bfloat16_t>): New explicit instantiations.
* include/bits/std_abs.h (abs): New overloads for
_Float{16,32,64,128} and __gnu_cxx::__bfloat16_t.
* include/bits/c++config (_GLIBCXX_LDOUBLE_IS_IEEE_BINARY128): Define
if long double is IEEE quad.
(__gnu_cxx::__bfloat16_t): New using.
* include/c_global/cmath (acos, asin, atan, atan2, ceil, cos, cosh,
exp, fabs, floor, fmod, frexp, ldexp, log, log10, modf, pow, sin,
sinh, sqrt, tan, tanh, fpclassify, isfinite, isinf, isnan, isnormal,
signbit, isgreater, isgreaterequal, isless, islessequal,
islessgreater, isunordered, acosh, asinh, atanh, cbrt, copysign, erf,
erfc, exp2, expm1, fdim, fma, fmax, fmin, hypot, ilogb, lgamma,
llrint, llround, log1p, log2, logb, lrint, lround, nearbyint,
nextafter, remainder, rint, round, scalbln, scalbn, tgamma, trunc,
lerp): New overloads with _Float{16,32,64,128} or
__gnu_cxx::__bfloat16_t types.
* config/os/gnu-linux/os_defines.h (_GLIBCXX_HAVE_FLOAT128_MATH):
Prepare for definition if glibc 2.26 and later implements *f128 APIs
but comment out the actual definition for now.
* include/ext/type_traits.h (__promote<_Float16>, __promote<_Float32>,
__promote<_Float64>, __promote<_Float128>,
__promote<__gnu_cxx::__bfloat16_t>): New specializations.
* include/Makefile.am (std_headers): Add stdfloat.
* include/Makefile.in: Regenerated.
* include/precompiled/stdc++.h: Include stdfloat.
* testsuite/18_support/headers/stdfloat/types_std.cc: New test.
* testsuite/18_support/headers/limits/synopsis_cxx23.cc: New test.
* testsuite/26_numerics/headers/cmath/c99_classification_macros_c++23.cc:
New test.
* testsuite/26_numerics/headers/cmath/functions_std_c++23.cc: New test.
* testsuite/26_numerics/numbers/4.cc: New test.
* testsuite/29_atomics/atomic_float/requirements_cxx23.cc: New test.
This reverts c1676651b6 and uses the
__extension__ keyword to prevent pedantic warnings instead of diagnostic
pragmas.
This also adds the __extension__ keyword in <limits> and <bits/random.h>
where there are some more warnings that I missed in the previous commit.
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
libstdc++-v3/ChangeLog:
* include/bits/cpp_type_traits.h (__INT_N): Use __extension__
instead of diagnostic pragmas.
* include/bits/functional_hash.h: Likewise.
* include/bits/iterator_concepts.h (__is_signed_int128)
(__is_unsigned_int128): Likewise.
* include/bits/max_size_type.h (__max_size_type): Likewise.
(numeric_limits<__max_size_type>): Likewise.
* include/bits/std_abs.h (abs): Likewise.
* include/bits/stl_algobase.h (__size_to_integer): Likewise.
* include/bits/uniform_int_dist.h (uniform_int_distribution):
Likewise.
* include/ext/numeric_traits.h (_GLIBCXX_INT_N_TRAITS):
Likewise.
* include/std/type_traits (__is_integral_helper<INT_N>)
(__is_signed_integer, __is_unsigned_integer)
(__make_unsigned<INT_N>, __make_signed<INT_N>): Likewise.
* include/std/limits (__INT_N): Add __extension__ keyword.
* include/bits/random.h (_Select_uint_least_t)
(random_device): Likewise.
With -std=c++NN -pedantic -Wsystem-headers there are warnings about the
use of __int128, which can be suppressed using diagnostic pragmas.
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
libstdc++-v3/ChangeLog:
* include/bits/cpp_type_traits.h: Add diagnostic pragmas around
uses of non-standard integer types.
* include/bits/functional_hash.h: Likewise.
* include/bits/iterator_concepts.h: Likewise.
* include/bits/max_size_type.h: Likewise.
* include/bits/std_abs.h: Likewise.
* include/bits/stl_algobase.h: Likewise.
* include/bits/uniform_int_dist.h: Likewise.
* include/ext/numeric_traits.h: Likewise.
* include/std/type_traits: Likewise.
This DR was already resolved for GCC 7.1 by the implementation of DR
2192, but we didn't have an explicit test for the behaviour that 2735
guarantees.
* doc/xml/manual/intro.xml: Document LWG 2735 status.
* include/bits/std_abs.h: Add comment about LWG 2735.
* testsuite/26_numerics/headers/cstdlib/dr2735.cc: New test.
From-SVN: r268867
PR libstdc++/77814
* include/bits/std_abs.h: Use "C++" language linkage.
* testsuite/17_intro/headers/c++2011/linkage.cc: Move <complex.h> to
the end. Add <stdalign.h>.
From-SVN: r240710