https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122374
Bug ID: 122374
Summary: ICE on assignment expression in requires clause in
copy constructor
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: eczbek.void at gmail dot com
Target Milestone: ---
https://godbolt.org/z/PeazsnK4n
Clang seems to accept this
```
template<int x>
struct S {
S() {}
S(const S&) requires(!requires { *this = 0; }) {}
};
int main() {
S<0> a;
auto b = a;
}
```
```
Using built-in specs.
COLLECT_GCC=/opt/compiler-explorer/gcc-snapshot/bin/g++
Target: x86_64-linux-gnu
Configured with: ../gcc-trunk-20251021/configure
--prefix=/opt/compiler-explorer/gcc-build/staging
--enable-libstdcxx-backtrace=yes --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,objc,obj-c++,go,d,rust,m2,cobol
--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-1ea18259a9cfb4dcee013a71e3f2dd349dc25ab6-binutils-2.44
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 16.0.0 20251021 (experimental)
(Compiler-Explorer-Build-gcc-1ea18259a9cfb4dcee013a71e3f2dd349dc25ab6-binutils-2.44)
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-masm=intel' '-fno-verbose-asm' '-S' '-std=c++20' '-v' '-freport-bug'
'-shared-libgcc' '-mtune=generic' '-march=x86-64' '-dumpdir' '/app/'
/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../libexec/gcc/x86_64-linux-gnu/16.0.0/cc1plus
-quiet -v -imultiarch x86_64-linux-gnu -iprefix
/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/x86_64-linux-gnu/16.0.0/
-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 -fno-verbose-asm -freport-bug -o /app/output.s
GNU C++20
(Compiler-Explorer-Build-gcc-1ea18259a9cfb4dcee013a71e3f2dd349dc25ab6-binutils-2.44)
version 16.0.0 20251021 (experimental) (x86_64-linux-gnu)
compiled by GNU C version 11.4.0, GMP version 6.3.0, MPFR version
4.2.2, MPC version 1.3.1, isl version isl-0.24-GMP
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
ignoring nonexistent directory
"/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/x86_64-linux-gnu/16.0.0/../../../../x86_64-linux-gnu/include"
ignoring duplicate directory
"/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/16.0.0/../../../../include/c++/16.0.0"
ignoring duplicate directory
"/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/16.0.0/../../../../include/c++/16.0.0/x86_64-linux-gnu"
ignoring duplicate directory
"/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/16.0.0/../../../../include/c++/16.0.0/backward"
ignoring duplicate directory
"/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/16.0.0/include"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring duplicate directory
"/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/16.0.0/include-fixed/x86_64-linux-gnu"
ignoring duplicate directory
"/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/16.0.0/include-fixed"
ignoring nonexistent directory
"/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/16.0.0/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/x86_64-linux-gnu/16.0.0/../../../../include/c++/16.0.0
/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/x86_64-linux-gnu/16.0.0/../../../../include/c++/16.0.0/x86_64-linux-gnu
/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/x86_64-linux-gnu/16.0.0/../../../../include/c++/16.0.0/backward
/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/x86_64-linux-gnu/16.0.0/include
/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/x86_64-linux-gnu/16.0.0/include-fixed/x86_64-linux-gnu
/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/x86_64-linux-gnu/16.0.0/include-fixed
/usr/local/include
/cefs/2d/2df80a36a18c6fc626c5c066_gcc-trunk-20251021/bin/../lib/gcc/../../include
/usr/include/x86_64-linux-gnu
/usr/include
End of search list.
Compiler executable checksum: 5c39a481e24d2e6b86f29b6a431373ad
<source>: In instantiation of 'S<x>::S(const S<x>&) requires
!requires{*(S<x>*)this =0;} [with int x = 0]':
required from 'S<x>::S(const S<x>&) requires !requires{*(S<x>*)this =0;} [with
int x = 0]'
<source>:5:41:
5 | S(const S&) requires(!requires { *this = 0; }) {}
| ~~~~~~^~~
required from here
<source>:10:11:
10 | auto b = a;
| ^
<source>:5:48: internal compiler error: in get, at cp/constraint.cc:2143
5 | S(const S&) requires(!requires { *this = 0; }) {}
| ~~~~~~^~~
0x28dfb38 diagnostics::context::diagnostic_impl(rich_location*,
diagnostics::metadata const*, diagnostics::option_id, char const*,
__va_list_tag (*) [1], diagnostics::kind)
???:0
0x28d492b internal_error(char const*, ...)
???:0
0xb07104 fancy_abort(char const*, int, char const*)
???:0
0xb99198 constraints_satisfied_p(tree_node*, tree_node*)
???:0
0xb423e6 build_new_op(op_location_t const&, tree_code, int, tree_node*,
tree_node*, tree_node*, tree_node*, tree_node**, int)
???:0
0xe273b9 cp_build_modify_expr(unsigned long, tree_node*, tree_code, tree_node*,
int)
???:0
0xe27ba7 build_x_modify_expr(unsigned long, tree_node*, tree_code, tree_node*,
tree_node*, int)
???:0
0xb97d06 tsubst_requires_expr(tree_node*, tree_node*, int, tree_node*)
???:0
0xb99198 constraints_satisfied_p(tree_node*, tree_node*)
???:0
0xb2880b build_new_method_call(tree_node*, tree_node*, vec<tree_node*, va_gc,
vl_embed>**, tree_node*, int, tree_node**, int)
???:0
0xb29f3d build_special_member_call(tree_node*, tree_node*, vec<tree_node*,
va_gc, vl_embed>**, tree_node*, int, int)
???:0
0xbbf9c8 ocp_convert(tree_node*, tree_node*, int, int, int)
???:0
0xc4263a build_aggr_init(tree_node*, tree_node*, int, int)
???:0
0xc0ce9e cp_finish_decl(tree_node*, tree_node*, bool, tree_node*, int,
cp_decomp*)
???:0
0xd3ff93 c_parse_file()
???:0
0xeb06b9 c_common_parse_file()
???:0
Please submit a full bug report, with preprocessed source.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
Preprocessed source stored into /tmp/cc391zCA.out file, please attach this to
your bugreport.
Compiler returned: 1
```
