https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70265
Bug ID: 70265 Summary: ICE on code with constexpr on x86_64-linux-gnu in tree check: expected statement_list, have nop_expr in tsi_start, at tree-iterator.h:42 Product: gcc Version: 6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: su at cs dot ucdavis.edu Target Milestone: --- The following valid code causes an ICE when compiled with the current GCC trunk on x86_64-linux-gnu in both 32-bit and 64-bit modes. It also seems to affect all 5.x. $ 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/6.0.0/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 6.0.0 20160317 (experimental) [trunk revision 234278] (GCC) $ $ g++-trunk -c small.cpp small2.cpp:10:20: in constexpr expansion of ‘foo(1)’ small2.cpp:10:33: internal compiler error: tree check: expected statement_list, have nop_expr in tsi_start, at tree-iterator.h:42 static_assert (foo (1) == 0, ""); ^ 0xfe2bdc tree_check_failed(tree_node const*, char const*, int, char const*, ...) ../../gcc-source-trunk/gcc/tree.c:9643 0x5d17ff tree_check ../../gcc-source-trunk/gcc/tree.h:3006 0x5d17ff tsi_start ../../gcc-source-trunk/gcc/tree-iterator.h:42 0x85382f tsi_start ../../gcc-source-trunk/gcc/cp/constexpr.c:3105 0x85382f cxx_eval_statement_list ../../gcc-source-trunk/gcc/cp/constexpr.c:3136 0x84d024 cxx_eval_loop_expr ../../gcc-source-trunk/gcc/cp/constexpr.c:3184 0x84d024 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:3842 0x8536b5 cxx_eval_statement_list ../../gcc-source-trunk/gcc/cp/constexpr.c:3152 0x84cf3a cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:3776 0x84d18a cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:3782 0x84c536 cxx_eval_call_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:1393 0x84d46b cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:3374 0x850fdd cxx_eval_binary_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:1617 0x84d395 cxx_eval_constant_expression ../../gcc-source-trunk/gcc/cp/constexpr.c:3624 0x853999 cxx_eval_outermost_constant_expr ../../gcc-source-trunk/gcc/cp/constexpr.c:3939 0x85669c maybe_constant_value_1 ../../gcc-source-trunk/gcc/cp/constexpr.c:4127 0x85669c maybe_constant_value(tree_node*, tree_node*) ../../gcc-source-trunk/gcc/cp/constexpr.c:4148 0x7c2465 finish_static_assert(tree_node*, tree_node*, unsigned int, bool) ../../gcc-source-trunk/gcc/cp/semantics.c:8681 0x741520 cp_parser_static_assert ../../gcc-source-trunk/gcc/cp/parser.c:13050 0x753339 cp_parser_block_declaration ../../gcc-source-trunk/gcc/cp/parser.c:12244 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. $ ------------------------------------ constexpr int foo (int p) { int t = 0; while (1) ; return t; } static_assert (foo (1) == 0, "");