[Bug c++/83817] New: [8 Regression]

["olegendo at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83817

            Bug ID: 83817
           Summary: [8 Regression]
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: olegendo at gcc dot gnu.org
  Target Milestone: ---
            Target: rx*-*-*
             Build: internal compiler error: tree check: expected
                    call_expr, have aggr_init_expr in
                    tsubst_copy_and_build, at cp/pt.c:17822

Compiling the following on RX with -O2 -std=c++14

#include <string>

struct message
{
  std::string m_content_data;
};


struct response : message { };
struct request : message { };

typedef response (*http_handler_func)(const request&);


struct http_handler
{
  const char* uri;
  http_handler_func func;
};

static response some_handler (const request&);

static const http_handler http_handlers_single[] =
{
  { "x", [] (const auto& r) { return some_handler (r); } },
};


results in
http_server_bug.cpp: In instantiation of 'static decltype (((const<lambda(const
auto:1&)>*)((const<lambda(const auto:1&)>*
const)0))->operator()(static_cast<const auto:1&>(<anonymous>)))<lambda(const
auto:1&)>::_FUN(const auto:1&) [with auto:1 = request; decltype
(((const<lambda(const auto:1&)>*)((const<lambda(const auto:1&)>*
const)0))->operator()(static_cast<const auto:1&>(<anonymous>))) = response]':
http_server_bug.cpp:25:56:   required from '<lambda(const auto:1&)>::operator
decltype (((const<lambda(const auto:1&)>*)((const<lambda(const auto:1&)>*
const)0))->operator()(static_cast<const auto:1&>(<anonymous>))) (*)(const
auto:1&)() const [with auto:1 = request; decltype (((const<lambda(const
auto:1&)>*)((const<lambda(const auto:1&)>*
const)0))->operator()(static_cast<const auto:1&>(<anonymous>))) = response]'
http_server_bug.cpp:26:1:   required from here
http_server_bug.cpp:25:56: internal compiler error: tree check: expected
call_expr, have aggr_init_expr in tsubst_copy_and_build, at cp/pt.c:17822
   { "x",  [] (const auto& r) { return some_handler (r); } },
                                                        ^
0x58ae34 tree_check_failed(tree_node const*, char const*, int, char const*,
...)
        ../../gcc-trunk/gcc/tree.c:9375
0x75721a tree_check(tree_node*, char const*, int, char const*, tree_code)
        ../../gcc-trunk/gcc/tree.h:3127
0x75721a tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
        ../../gcc-trunk/gcc/cp/pt.c:17822
0x75a163 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
        ../../gcc-trunk/gcc/cp/pt.c:16765
0x75944c tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
        ../../gcc-trunk/gcc/cp/pt.c:15996
0x759693 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
        ../../gcc-trunk/gcc/cp/pt.c:16249
0x795aee instantiate_decl(tree_node*, bool, bool)
        ../../gcc-trunk/gcc/cp/pt.c:23311
0x79d1e9 instantiate_pending_templates(int)
        ../../gcc-trunk/gcc/cp/pt.c:23427
0x67dd02 c_parse_final_cleanups()
        ../../gcc-trunk/gcc/cp/decl2.c:4705