[Bug c++/83445] New: conversion function has too high priority in overload resolution
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83445
Bug ID: 83445
Summary: conversion function has too high priority in overload
resolution
Product: gcc
Version: 7.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: omawarisan.bokudesu at live dot jp
Target Milestone: ---
In the following program, overload resolution in the
direct-initialization of `target` from `source` (in the main function)
should select `Target(Source const&)` directly,
but gcc 7.2.0 and trunk with -std=c++17 uses `Source::operator Target()` .
I believe the former should be selected because a standard conversion sequence
is always better than a user-defined conversion sequence.
command: g++ test.cpp -std=c++17 -pedantic test.cpp
expected behavior: prints "OK"
actual behavior: prints "Bad"
#include
struct Source;
struct Target
{
Target() = default;
Target(Source const&){
std::printf("OK\n");
value = 0;
}
int value = -1;
};
struct Source
{
operator Target(){
std::printf("Bad\n");
Target target;
target.value = 1;
return target;
}
};
int main()
{
Source source;
Target target{source};
std::printf("v = %d\n", target.value);
}
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/data2/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/8.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /data2/gcc-trunk/gcc/configure --prefix=/data2/gcc-trunk
--enable-languages=c,c++ --disable-multilib
Thread model: posix
gcc version 8.0.0 20171215 (experimental) (GCC)
[Bug c++/57005] New: alias template's pseudo-destructor is rejected
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57005
Bug #: 57005
Summary: alias template's pseudo-destructor is rejected
Classification: Unclassified
Product: gcc
Version: 4.9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: omawarisan.bokud...@live.jp
g++ -std=c++11 does not allow the following pseudo-destructor call.
template class T
using type = T;
int main()
{
typeint().~typeint();
}
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/home/user/gcc-trunk/libexec/gcc/x86_64-unknown-linux-gnu/4.9.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc/configure --prefix=/home/user/gcc-trunk
--disable-bootstrap --disable-multilib --enable-languages=c,c++,fortran
--with-gmp=/home/user/gcc-trunk/src/build/backends
--with-mpfr=/home/user/gcc-trunk/src/build/backends
--with-mpc=/home/user/gcc-trunk/src/build/backends
Thread model: posix
gcc version 4.9.0 20130419 (experimental) (GCC)
[Bug c++/56388] New: catch(...) in lambda rejected
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56388
Bug #: 56388
Summary: catch(...) in lambda rejected
Classification: Unclassified
Product: gcc
Version: 4.8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: omawarisan.bokud...@live.jp
g++ -std=c++11 rejects the following program:
int main()
{
bool /*const*/ condition = false;
[]{
try{}
catch(...){
if(condition){}
}
}();
}
If the condition variable is const, the compilation successes.
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/home/user/gcc-trunk/libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc/configure --prefix=/home/user/gcc-trunk
--disable-bootstrap --disable-multilib --enable-languages=c,c++,fortran
--with-gmp=/home/user/gcc-trunk/src/build/backends
--with-mpfr=/home/user/gcc-trunk/src/build/backends
--with-mpc=/home/user/gcc-trunk/src/build/backends
Thread model: posix
gcc version 4.8.0 20130219 (experimental) (GCC)
[Bug c++/53484] New: [c++11] Wrong auto in lambdas in function templates
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53484
Bug #: 53484
Summary: [c++11] Wrong auto in lambdas in function templates
Classification: Unclassified
Product: gcc
Version: 4.8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: omawarisan.bokud...@live.jp
In the following program, auto is deduced to be int, while int is expected.
template class T
void f(T x){
[]{
std::cout x std::endl;
auto y = x;
y = 100;
std::cout x std::endl;
}();
}
int main(){ f(0); }
output:
0
100
In non-template functions, it doesn't occur.
revision r187865
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/home/user/gcc-trunk/libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-trunk/configure --prefix=/home/user/gcc-trunk
--disable-bootstrap --disable-multilib --enable-languages=c,c++,fortran
--with-gmp=/home/user/gcc-trunk/src/build/backends
--with-mpfr=/home/user/gcc-trunk/src/build/backends
--with-mpc=/home/user/gcc-trunk/src/build/backends
Thread model: posix
gcc version 4.8.0 20120525 (experimental) (GCC)
