https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71972
Bug ID: 71972 Summary: ICE with "-std=c++14" on x86_64-linux-gnu (internal compiler error: Segmentation fault, cxx_eval_store_expression) Product: gcc Version: 7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: chengniansun at gmail dot com Target Milestone: --- $ g++-trunk -v Using built-in specs. COLLECT_GCC=g++-trunk COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../gcc-source-trunk/configure --enable-languages=c,c++,lto --prefix=/usr/local/gcc-trunk --disable-bootstrap Thread model: posix gcc version 7.0.0 20160722 (experimental) [trunk revision 238645] (GCC) $ $ g++-trunk -std=c++14 small.C small.C: In instantiation of ‘auto concat(S<N>, S<M>) [with int N = 1; int M = 1]’: small.C:14:16: required from here small.C:10:59: in constexpr expansion of ‘s.S<N>::S<1>(s1.S<1>::data)’ small.C:10:59: internal compiler error: Segmentation fault template <int N, int M> auto concat(S<N> s1, S<M>) { S<1> s(s1.data); } ^ 0xdb18cf crash_signal ../../gcc-source-trunk/gcc/toplev.c:335 0x8be3b5 cxx_eval_store_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:3238 0x8bbf7d cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:3741 0x8baee6 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:4026 0x8bb120 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:3780 0x8bb120 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:3780 0x8c1306 cxx_eval_statement_list ../../gcc-source-trunk/gcc/cp/constexpr.c:3438 0x8bb6e0 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:4082 0x8bbe8a cxx_eval_loop_expr ../../gcc-source-trunk/gcc/cp/constexpr.c:3470 0x8bbe8a cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:4159 0x8c1306 cxx_eval_statement_list ../../gcc-source-trunk/gcc/cp/constexpr.c:3438 0x8bb6e0 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:4082 0x8c1306 cxx_eval_statement_list ../../gcc-source-trunk/gcc/cp/constexpr.c:3438 0x8bb6e0 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:4082 0x8bb241 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:4088 0x8bb241 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:4088 0x8c1306 cxx_eval_statement_list ../../gcc-source-trunk/gcc/cp/constexpr.c:3438 0x8bb6e0 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:4082 0x8bb241 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:4088 0x8c1306 cxx_eval_statement_list ../../gcc-source-trunk/gcc/cp/constexpr.c:3438 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <http://gcc.gnu.org/bugs.html> for instructions. $ $ cat small.C typedef int size_t; template <int N> struct S { template <size_t M> constexpr S(char (&)[M]) : data{} { for (size_t i = 0;;) data[i] = data[i]; } char data[N]; }; template <int N> S<N> s(char const (&)[N]); template <int N, int M> auto concat(S<N> s1, S<M>) { S<1> s(s1.data); } int main() { auto s1 = s(""); auto s2 = s(""); concat(s1, s2); return 0; } $