moving average example causes ice in gcc7

[JeffGarland]

[ 85%] Building CXX object CMakeFiles/51_moving_average.dir/51_moving_average.cpp.o /home/jeff/devtools/gcc7/install/usr/local/bin/g++ -I/home/jeff/dev/git/range_by_example/rangev3 -std=c++17 -Wall -Wextra -Werror -Wno-missing-braces -o CMakeFiles/51_moving_average.dir/51_moving_average.cpp.o -c /home/jeff/dev/git/range_by_example/51_moving_average.cpp In file included from /home/jeff/dev/git/range_by_example/rangev3/range/v3/core.hpp:22:0, from /home/jeff/dev/git/range_by_example/rangev3/range/v3/all.hpp:17, from /home/jeff/dev/git/range_by_example/51_moving_average.cpp:2: /home/jeff/dev/git/range_by_example/rangev3/range/v3/view_adaptor.hpp: In instantiation of ‘X ranges::v3::adaptor_cursor<BaseIt, Adapt>::iter_move_(ranges::v3::detail::any) const [with A = ranges::v3::sliding_view<ranges::v3::iterator_range<const double*, const double*>, (ranges::v3::sliding_view_detail::cache)0>::adaptor; R = ranges::v3::iterator_range<const double*, const double*>; X = ranges::v3::iterator_range<const double*, const double*>; BaseIter = const double*; Adapt = ranges::v3::sliding_view<ranges::v3::iterator_range<const double*, const double*>, (ranges::v3::sliding_view_detail::cache)0>::adaptor; ranges::v3::detail::any = ranges::v3::detail::any_]’:

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/home/jeff/dev/git/range_by_example/51_moving_average.cpp:27:12: required from here /home/jeff/dev/git/range_by_example/rangev3/range/v3/view_adaptor.hpp:356:64: internal compiler error: in build_over_call, at cp/call.c:7977 return static_cast<X &&>(second().read(first())); ^ 0x601feb build_over_call ../../src/gcc/cp/call.c:7974 0x602b9e build_new_method_call_1 ../../src/gcc/cp/call.c:8800 0x602b9e build_new_method_call(tree_node*, tree_node*, vec<tree_node*, va_gc, vl_embed>, tree_node*, int, tree_node, int) ../../src/gcc/cp/call.c:8869 0x604009 build_special_member_call(tree_node*, tree_node*, vec<tree_node*, va_gc, vl_embed>**, tree_node*, int, int) ../../src/gcc/cp/call.c:8398 0x605455 build_temp ../../src/gcc/cp/call.c:6482 0x605455 convert_like_real ../../src/gcc/cp/call.c:6900 0x60683c perform_implicit_conversion_flags(tree_node*, tree_node*, int, int) ../../src/gcc/cp/call.c:10071 0x77638f check_return_expr(tree_node*, bool*) ../../src/gcc/cp/typeck.c:9002 0x7a9dee finish_return_stmt(tree_node*) ../../src/gcc/cp/semantics.c:878 0x67bdb4 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool) ../../src/gcc/cp/pt.c:15665 0x67d1fd tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool) ../../src/gcc/cp/pt.c:15655 0x67d890 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool) ../../src/gcc/cp/pt.c:15879 0x67a1c4 instantiate_decl(tree_node*, int, bool) ../../src/gcc/cp/pt.c:22815 0x6ba15b instantiate_pending_templates(int) ../../src/gcc/cp/pt.c:22936 0x6fce48 c_parse_final_cleanups() ../../src/gcc/cp/decl2.c:4522 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.