https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85210
Bug ID: 85210 Summary: ICE with broken structured binding in template Product: gcc Version: 8.0 Status: UNCONFIRMED Keywords: error-recovery, ice-on-invalid-code Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: reichelt at gcc dot gnu.org Target Milestone: --- The following invalid code snippet (compiled with "-std=c++1z") triggers an ICE since GCC 7.1.0 (structured bindings were introduced): ============================ struct A { int i; }; template<int> void foo(int j) { auto [j] = A{j}; } void bar() { foo<0>(0); } ============================ bug.cc: In function 'void foo(int)': bug.cc:5:10: error: declaration of 'auto j' shadows a parameter auto [j] = A{j}; ^ bug.cc: In instantiation of 'void foo(int) [with int <anonymous> = 0]': bug.cc:10:11: required from here bug.cc:5:8: internal compiler error: in fit_decomposition_lang_decl, at cp/lex.c:724 auto [j] = A{j}; ^~~ 0x61802a fit_decomposition_lang_decl(tree_node*, tree_node*) ../../gcc/gcc/cp/lex.c:724 0x8a2868 cp_finish_decomp(tree_node*, tree_node*, unsigned int) ../../gcc/gcc/cp/decl.c:7545 0x9746fd tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool) ../../gcc/gcc/cp/pt.c:16409 0x96f15f tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool) ../../gcc/gcc/cp/pt.c:16561 0x96e2f8 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool) ../../gcc/gcc/cp/pt.c:16249 0x96e2f8 instantiate_decl(tree_node*, bool, bool) ../../gcc/gcc/cp/pt.c:23659 0x9932db instantiate_pending_templates(int) ../../gcc/gcc/cp/pt.c:23775 0x8b893b c_parse_final_cleanups() ../../gcc/gcc/cp/decl2.c:4724 Please submit a full bug report, [etc.]