[Bug libstdc++/48365] New: Non-constant references in std::valarray::operator
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48365 Summary: Non-constant references in std::valarray::operator Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ AssignedTo: unassig...@gcc.gnu.org ReportedBy: de...@mail.ru Created attachment 23819 -- http://gcc.gnu.org/bugzilla/attachment.cgi?id=23819 Test code When calling valarray*scalar arithmetic operators, where scalar is the element of valarray, it is modified during execution, thus influencig the result, though STL definition says that parameters of the operator are const references, and the result is the new valarray object. Attached is the code that produces output 4:12, while 4:6 expected, even when compiled with -O0.
[Bug c++/52869] [DR 1207] "this" not being allowed in noexcept clauses
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52869
denin at mail dot ru changed:
What|Removed |Added
CC||denin at mail dot ru
--- Comment #6 from denin at mail dot ru ---
Reproduced in 8.1.1:
$ cat nyan.cpp
struct Nyan {
constexpr Nyan ++() noexcept { return *this; }
constexpr void omg() noexcept(noexcept(++*this)) {}
};
int main() {}
$ g++ -Wall -Wextra nyan.cpp
nyan.cpp:3:44: error: invalid use of ‘this’ at top level
constexpr void omg() noexcept(noexcept(++*this)) {}
^~~~
$ clang++ nyan.cpp
$ g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/8.1.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /build/gcc/src/gcc/configure --prefix=/usr --libdir=/usr/lib
--libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info
--with-bugurl=https://bugs.archlinux.org/
--enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared
--enable-threads=posix --enable-libmpx --with-system-zlib --with-isl
--enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu
--disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object
--enable-linker-build-id --enable-lto --enable-plugin
--enable-install-libiberty --with-linker-hash-style=gnu
--enable-gnu-indirect-function --enable-multilib --disable-werror
--enable-checking=release --enable-default-pie --enable-default-ssp
Thread model: posix
gcc version 8.1.1 20180531 (GCC)
$ uname -a
Linux home 4.17.10-1-ARCH #1 SMP PREEMPT Wed Jul 25 11:23:00 UTC 2018 x86_64
GNU/Linux
[Bug libstdc++/86963] New: std::tuple incorrectly assigned
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86963
Bug ID: 86963
Summary: std::tuple incorrectly assigned
Product: gcc
Version: 8.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: denin at mail dot ru
Target Milestone: ---
$ cat meow.cpp
#include
#include
struct S {
S =(S const &) = delete;
S =(S &&) = delete;
};
static_assert(!std::is_move_assignable_v>);
$ g++ meow.cpp
meow.cpp:8:15: error: static assertion failed
static_assert(!std::is_move_assignable_v>);
^~~~
Despite tuple's elements being not assignable at all, tuple itself is
incorrectly considered assignable, due to non-SFINAE protected operator= in
class definition. Thus, the following code breaks on 'f = std::move(g);':
template void mv_assign(T , T &) {
if constexpr(std::is_move_assignable_v>) left =
std::move(right);
}
int main() {
std::tuple f, g;
mv_assign(f, std::move(g));
}
ENVIRONMENT
$ g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/8.1.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /build/gcc/src/gcc/configure --prefix=/usr --libdir=/usr/lib
--libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info
--with-bugurl=https://bugs.archlinux.org/
--enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared
--enable-threads=posix --enable-libmpx --with-system-zlib --with-isl
--enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu
--disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object
--enable-linker-build-id --enable-lto --enable-plugin
--enable-install-libiberty --with-linker-hash-style=gnu
--enable-gnu-indirect-function --enable-multilib --disable-werror
--enable-checking=release --enable-default-pie --enable-default-ssp
Thread model: posix
gcc version 8.1.1 20180531 (GCC)
$ uname -a
Linux home 4.17.10-1-ARCH #1 SMP PREEMPT Wed Jul 25 11:23:00 UTC 2018 x86_64
GNU/Linux
[Bug c++/52869] [DR 1207] "this" not being allowed in noexcept clauses
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52869 --- Comment #15 from denin at mail dot ru --- (In reply to Marek Polacek from comment #14) > This is actually another problem, one that is tracked in PR86476. So context closure is unduly greedy: members defined above are available while those from below are not? Funny indeed.
[Bug c++/52869] [DR 1207] "this" not being allowed in noexcept clauses
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52869
--- Comment #16 from denin at mail dot ru ---
(In reply to Marek Polacek from comment #14)
> This is actually another problem, one that is tracked in PR86476.
Hmm.
$ cat wat.cpp
struct Omg {
void f() {}
void g() noexcept(noexcept(f())) {}
};
$ g++ wat.cpp
wat.cpp:3:31: error: cannot call member function ‘void Omg::f()’ without object
void g() noexcept(noexcept(f())) {}
^
$ g++ -v |& grep version
gcc version 8.2.1 20181127 (GCC)
