https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108755
Bug ID: 108755 Summary: ICE in use_thunk at cp/method.cc:317 Product: gcc Version: 12.2.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: ramir.sultano at ya dot ru Target Milestone: --- gcc version 12.2.1 20230111 (GCC) 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-build-config=bootstrap-lto --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-libstdcxx-backtrace --enable-link-serialization=1 --enable-linker-build-id --enable-lto --enable-multilib --enable-plugin --enable-shared --enable-threads=posix --disable-libssp --disable-libstdcxx-pch --disable-werror The complete command line that triggers the bug: g++ main.cxx The compiler output (error messages, warnings, etc.): main.cxx: In instantiation of ‘constexpr X AB<X>::b() const [with X = bool]’: main.cxx:21:23: required from here main.cxx:14:49: internal compiler error: in use_thunk, at cp/method.cc:317 14 | constexpr X b() const override { return {}; }; | ^ 0x19e2ee8 internal_error(char const*, ...) ???:0 0x65443c fancy_abort(char const*, int, char const*) ???:0 0x813cb0 emit_associated_thunks(tree_node*) ???:0 0x7db493 instantiate_decl(tree_node*, bool, bool) ???:0 0x6a7b96 maybe_constant_value(tree_node*, tree_node*, bool) ???:0 0x84a9ba cp_build_binary_op(op_location_t const&, tree_code, tree_node*, tree_node*, int) ???:0 0x69acb2 build_new_op(op_location_t const&, tree_code, int, tree_node*, tree_node*, tree_node*, tree_node*, tree_node**, int) ???:0 0x852fbb build_x_binary_op(op_location_t const&, tree_code, tree_node*, tree_code, tree_node*, tree_code, tree_node*, tree_node**, int) ???:0 0x7c7d9c c_parse_file() ???:0 0x8dd47d c_common_parse_file() ???:0 The preprocessed file (*.i*) that triggers the bug, generated by adding -save-temps to the complete compilation command: template <class X> struct A { constexpr virtual X a() const = 0; }; template <class X> struct B { constexpr virtual X b() const = 0; }; template <class X> struct AB : public A<X>, public B<X> { constexpr X a() const override { return {}; }; constexpr X b() const override { return {}; }; }; int main() { using x_type = bool; constexpr AB<x_type> ab{}; static_assert(ab.a() == x_type{}); static_assert(ab.b() == x_type{}); return 0; } Notes: possible duplicate of [91846](https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91846)