https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105419
Bug ID: 105419
Summary: [11 Regression] std::initializer_list<T> constructor
invalid in C++20 mode
Product: gcc
Version: 11.3.0
Status: UNCONFIRMED
Keywords: rejects-valid
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: whisperity at gmail dot com
Target Milestone: ---
The following code is rejected when compiled with `-std=c++20` if using G++
11.y. `-std=c++17` accepts it.
G++ 10.y accepts in both C++17 and C++20 version.
#include <initializer_list>
template <class T, class K = long long int>
struct C
{
C<T, K>(std::initializer_list<T> L) {}
};
int main()
{
C<int> Cont = {1, 2};
}
Platform: X86_64 (amd64) Linux (specifically Ubuntu 20.04 LTS)
Godbolt: http://godbolt.org/z/rrbae9P5d
Compiler versions:
Using built-in specs.
COLLECT_GCC=/opt/compiler-explorer/gcc-10.3.0/bin/g++
Target: x86_64-linux-gnu
Configured with: ../gcc-10.3.0/configure
--prefix=/opt/compiler-explorer/gcc-build/staging --build=x86_64-linux-gnu
--host=x86_64-linux-gnu --target=x86_64-linux-gnu --disable-bootstrap
--enable-multiarch --with-abi=m64 --with-multilib-list=m32,m64,mx32
--enable-multilib --enable-clocale=gnu
--enable-languages=c,c++,fortran,ada,go,d --enable-ld=yes --enable-gold=yes
--enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-linker-build-id
--enable-lto --enable-plugins --enable-threads=posix
--with-pkgversion=Compiler-Explorer-Build
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 10.3.0 (Compiler-Explorer-Build)
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-masm=intel' '-S' '-std=c++17' '-v' '-shared-libgcc' '-mtune=generic'
'-march=x86-64'
/opt/compiler-explorer/gcc-10.3.0/bin/../libexec/gcc/x86_64-linux-gnu/10.3.0/cc1plus
-quiet -v -imultiarch x86_64-linux-gnu -iprefix
/opt/compiler-explorer/gcc-10.3.0/bin/../lib/gcc/x86_64-linux-gnu/10.3.0/
-D_GNU_SOURCE <source> -quiet -dumpbase example.cpp -masm=intel -mtune=generic
-march=x86-64 -auxbase-strip /app/output.s -g -std=c++17 -version
-fdiagnostics-color=always -o /app/output.s
GNU C++17 (Compiler-Explorer-Build) version 10.3.0 (x86_64-linux-gnu)
compiled by GNU C version 7.5.0, GMP version 6.1.0, MPFR version 3.1.4,
MPC version 1.0.3, isl version isl-0.18-GMP
Using built-in specs.
COLLECT_GCC=/opt/compiler-explorer/gcc-11.3.0/bin/g++
Target: x86_64-linux-gnu
Configured with: ../gcc-11.3.0/configure
--prefix=/opt/compiler-explorer/gcc-build/staging --build=x86_64-linux-gnu
--host=x86_64-linux-gnu --target=x86_64-linux-gnu --disable-bootstrap
--enable-multiarch --with-abi=m64 --with-multilib-list=m32,m64,mx32
--enable-multilib --enable-clocale=gnu
--enable-languages=c,c++,fortran,ada,go,d --enable-ld=yes --enable-gold=yes
--enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-linker-build-id
--enable-lto --enable-plugins --enable-threads=posix
--with-pkgversion=Compiler-Explorer-Build-gcc--binutils-2.36.1
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 11.3.0 (Compiler-Explorer-Build-gcc--binutils-2.36.1)
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-masm=intel' '-S' '-std=c++20' '-v' '-shared-libgcc' '-mtune=generic'
'-march=x86-64' '-dumpdir' '/app/'
/opt/compiler-explorer/gcc-11.3.0/bin/../libexec/gcc/x86_64-linux-gnu/11.3.0/cc1plus
-quiet -v -imultiarch x86_64-linux-gnu -iprefix
/opt/compiler-explorer/gcc-11.3.0/bin/../lib/gcc/x86_64-linux-gnu/11.3.0/
-D_GNU_SOURCE <source> -quiet -dumpdir /app/ -dumpbase output.cpp -dumpbase-ext
.cpp -masm=intel -mtune=generic -march=x86-64 -g -std=c++20 -version
-fdiagnostics-color=always -o /app/output.s
GNU C++20 (Compiler-Explorer-Build-gcc--binutils-2.36.1) version 11.3.0
(x86_64-linux-gnu)
compiled by GNU C version 7.5.0, GMP version 6.1.0, MPFR version 3.1.6,
MPC version 1.0.3, isl version isl-0.18-GMP
