[Bug c++/70540] New: ICE on invalid code on x86_64-linux-gnu in cxx_incomplete_type_diagnostic, at cp/typeck2.c:569

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70540

            Bug ID: 70540
           Summary: ICE on invalid code on x86_64-linux-gnu in
                    cxx_incomplete_type_diagnostic, at cp/typeck2.c:569
           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 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 is a regression from 5.3.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 20160404 (experimental) [trunk revision 234712] (GCC) 
$ 
$ g++-5.3 -c small.cpp
small.cpp: In function ‘void foo()’:
small.cpp:4:8: error: ‘f’ does not name a type
   auto f = [&] { return f; };
        ^
$ 
$ g++-trunk -c small.cpp
small.cpp: In lambda function:
small.cpp:4:25: error: use of ‘f’ before deduction of ‘auto’
   auto f = [&] { return f; };
                         ^
small.cpp:4:25: error: use of ‘foo()::<lambda()>::<f capture>’ before deduction
of ‘auto’
small.cpp:4:28: internal compiler error: in cxx_incomplete_type_diagnostic, at
cp/typeck2.c:569
   auto f = [&] { return f; };
                            ^
0x6ce8e3 cxx_incomplete_type_diagnostic(tree_node const*, tree_node const*,
diagnostic_t)
        ../../gcc-source-trunk/gcc/cp/typeck2.c:569
0x765f99 complete_type_or_maybe_complain(tree_node*, tree_node*, int)
        ../../gcc-source-trunk/gcc/cp/typeck.c:150
0x7c37fc apply_deduced_return_type(tree_node*, tree_node*)
        ../../gcc-source-trunk/gcc/cp/semantics.c:9226
0x7342a2 cp_parser_lambda_body
        ../../gcc-source-trunk/gcc/cp/parser.c:10256
0x7342a2 cp_parser_lambda_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:9756
0x734c9c cp_parser_primary_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:4933
0x736d26 cp_parser_postfix_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:6690
0x73fe6c cp_parser_unary_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:7988
0x7406c7 cp_parser_cast_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:8665
0x740cc5 cp_parser_binary_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:8767
0x7415b0 cp_parser_assignment_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:9055
0x7419ea cp_parser_constant_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:9323
0x742174 cp_parser_initializer_clause
        ../../gcc-source-trunk/gcc/cp/parser.c:20793
0x74391b cp_parser_initializer
        ../../gcc-source-trunk/gcc/cp/parser.c:20734
0x752bce cp_parser_init_declarator
        ../../gcc-source-trunk/gcc/cp/parser.c:18604
0x7532b0 cp_parser_simple_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:12379
0x7535c1 cp_parser_block_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:12248
0x754018 cp_parser_declaration_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:11860
0x7326db cp_parser_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:10528
0x732ffc cp_parser_statement_seq_opt
        ../../gcc-source-trunk/gcc/cp/parser.c:10806
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.
$ 


----------------------------------


void
foo ()
{
  auto f = [&] { return f; };
}