https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105375
Bug ID: 105375
Summary: std::packaged_task has no deduction guide.
Product: gcc
Version: 11.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: raldone01 at gmail dot com
Target Milestone: ---
According to cppreference
https://en.cppreference.com/w/cpp/thread/packaged_task/deduction_guides
std::packaged_task should have a deduction guide.
The example listed on their page does not compile.
gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/11.2.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /build/gcc/src/gcc/configure
--enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++,d --enable-bootstrap
--prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man
--infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/
--with-linker-hash-style=gnu --with-system-zlib --enable-__cxa_atexit
--enable-cet=auto --enable-checking=release --enable-clocale=gnu
--enable-default-pie --enable-default-ssp --enable-gnu-indirect-function
--enable-gnu-unique-object --enable-linker-build-id --enable-lto
--enable-multilib --enable-plugin --enable-shared --enable-threads=posix
--disable-libssp --disable-libstdcxx-pch --disable-werror
--with-build-config=bootstrap-lto --enable-link-serialization=1
gdc_include_dir=/usr/include/dlang/gdc
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 11.2.0 (GCC)
System type: Ubuntu WSL
Command line: c++ -Wall -Wextra -g -std=gnu++20 -o lin.obj -c main.cpp
Expected behavior: The snipped from cppreference compiles.
Actual behavior: The deduction guide for packaged_task is missing?
int func(double) { return 0; }
int main() {
std::packaged_task f{func}; // deduces packaged_task<int(double)>
int i = 5;
std::packaged_task g = [&](double) { return i; }; // deduces
packaged_task<int(double)>
}
As std::function has deduction guides shouldn't std::packaged_task have some
too?
