https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68530
Bug ID: 68530 Summary: [C++14] sorry, unimplemented: unexpected AST of kind loop_expr Product: gcc Version: 6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: lucdanton at free dot fr Target Milestone: --- Possibly related to PR c++/68206, which could also be exhibiting both this and a potentially unrelated ICE. $ g++-trunk --version g++-trunk (GCC) 6.0.0 20151125 (experimental) Copyright (C) 2015 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ cat main.cpp struct thing { void foo() {} }; template<typename> constexpr int count() { auto item = thing {}; for(; (item.foo(), false);); return 0; } int main() { static_assert( count<int>() == 0, "" ); } $ g++-trunk -std=c++14 main.cpp main.cpp: In function 'int main()': main.cpp:15:5: error: non-constant condition for static assertion static_assert( count<int>() == 0, "" ); ^~~~~~~~~~~~~ main.cpp:15:30: error: 'constexpr int count() [with <template-parameter-1-1> = int]' called in a constant expression static_assert( count<int>() == 0, "" ); ^ main.cpp:6:15: note: 'constexpr int count() [with <template-parameter-1-1> = int]' is not usable as a constexpr function because: constexpr int count() ^~~~~ main.cpp:6:15: sorry, unimplemented: unexpected AST of kind loop_expr main.cpp:6: confused by earlier errors, bailing out