https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99132
Bug ID: 99132 Summary: ICE in C++20 mode for constexpr not_null evaluation -- in cxx_eval_indirect_ref, at cp/constexpr.c:4905 Product: gcc Version: 11.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: bobmiller at nvidia dot com Target Milestone: --- Usage of gsl-lite::not_null can cause an internal compiler error. Minimal online example: https://godbolt.org/z/Y8n93K I also intend to report this to the gsl-lite maintainer, but I don't believe their code should trigger an ICE regardless. My system is x86-linux-amd64. I confirmed in current trunk, commit hash 24bf79f1798ad1d64812709001d2d11cd3e6849f The attached preprocessed output (a-test.ii) was built with the following command: g++-11 -v -save-temps --std=c++20 test.cpp Full output: -------------------------------------------------- Using built-in specs. COLLECT_GCC=/home/bob/bin/g++-11 COLLECT_LTO_WRAPPER=/home/bob/libexec/gcc/x86_64-linux-gnu/11.0.0/lto-wrapper Target: x86_64-linux-gnu Configured with: ../gcc/configure -v --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu --prefix=/home/bob/ --enable-checking=release --enable-languages=c,c++ --disable-multilib --program-suffix=-11 Thread model: posix Supported LTO compression algorithms: zlib gcc version 11.0.0 20210217 (experimental) (GCC) COLLECT_GCC_OPTIONS='-v' '-save-temps' '-std=c++20' '-shared-libgcc' '-mtune=generic' '-march=x86-64' '-dumpdir' 'a-' /home/bob/libexec/gcc/x86_64-linux-gnu/11.0.0/cc1plus -E -quiet -v -imultiarch x86_64-linux-gnu -D_GNU_SOURCE /home/bob/test.cpp -mtune=generic -march=x86-64 -std=c++20 -fpch-preprocess -o a-test.ii ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu" ignoring nonexistent directory "/home/bob/lib/gcc/x86_64-linux-gnu/11.0.0/../../../../x86_64-linux-gnu/include" #include "..." search starts here: #include <...> search starts here: /home/bob/lib/gcc/x86_64-linux-gnu/11.0.0/../../../../include/c++/11.0.0 /home/bob/lib/gcc/x86_64-linux-gnu/11.0.0/../../../../include/c++/11.0.0/x86_64-linux-gnu /home/bob/lib/gcc/x86_64-linux-gnu/11.0.0/../../../../include/c++/11.0.0/backward /home/bob/lib/gcc/x86_64-linux-gnu/11.0.0/include /usr/local/include /home/bob/include /home/bob/lib/gcc/x86_64-linux-gnu/11.0.0/include-fixed /usr/include/x86_64-linux-gnu /usr/include End of search list. COLLECT_GCC_OPTIONS='-v' '-save-temps' '-std=c++20' '-shared-libgcc' '-mtune=generic' '-march=x86-64' '-dumpdir' 'a-' /home/bob/libexec/gcc/x86_64-linux-gnu/11.0.0/cc1plus -fpreprocessed a-test.ii -quiet -dumpdir a- -dumpbase test.cpp -dumpbase-ext .cpp -mtune=generic -march=x86-64 -std=c++20 -version -o a-test.s GNU C++20 (GCC) version 11.0.0 20210217 (experimental) (x86_64-linux-gnu) compiled by GNU C version 11.0.0 20210216 (experimental), GMP version 6.1.0, MPFR version 3.1.4, MPC version 1.0.3, isl version isl-0.18-GMP GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072 GNU C++20 (GCC) version 11.0.0 20210217 (experimental) (x86_64-linux-gnu) compiled by GNU C version 11.0.0 20210216 (experimental), GMP version 6.1.0, MPFR version 3.1.4, MPC version 1.0.3, isl version isl-0.18-GMP GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072 Compiler executable checksum: 4db0a130394a49defb276090de10ab74 /home/bob/test.cpp: In member function ‘virtual void Source::attachSink(gsl::not_null<Sink*>)’: /home/bob/test.cpp:15:13: in ‘constexpr’ expansion of ‘sink.gsl::not_null<Sink*>::operator->()’ /home/bob/test.cpp:16:5: internal compionline example: https://godbolt.org/z/Y8n93K ler error: in cxx_eval_indirect_ref, at cp/constexpr.c:4905 16 | } | ^ 0x6649a2 cxx_eval_indirect_ref ../../gcc/gcc/cp/constexpr.c:4905 0x6649a2 cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6362 0x6dfc1a cxx_eval_component_reference ../../gcc/gcc/cp/constexpr.c:3797 0x6dfc1a cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6538 0x6dfc1a cxx_eval_component_reference ../../gcc/gcc/cp/constexpr.c:3797 0x6dfc1a cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6538 0x6dfa23 cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6634 0x6e8875 cxx_eval_binary_expression ../../gcc/gcc/cp/constexpr.c:3122 0x6df609 cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6500 0x6e1889 cxx_eval_conditional_expression ../../gcc/gcc/cp/constexpr.c:3232 0x6e1889 cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6581 0x6e04e0 cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6309 0x6e003c cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6320 0x6e0c26 cxx_eval_statement_list ../../gcc/gcc/cp/constexpr.c:5712 0x6e0c26 cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6777 0x6de835 cxx_eval_call_expression ../../gcc/gcc/cp/constexpr.c:2712 0x6dff56 cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6142 0x6e1ce1 cxx_eval_indirect_ref ../../gcc/gcc/cp/constexpr.c:4880 0x6e1ce1 cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6362 0x6dfa23 cxx_eval_constant_expression ../../gcc/gcc/cp/constexpr.c:6634 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <https://gcc.gnu.org/bugs/> for instructions. ---------------------------------------------------