[Bug c++/72800] New: ICE on invalid C++14 code with initialized lambda capture: tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in add_capture, at cp/lambda.c:505

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72800

            Bug ID: 72800
           Summary: ICE on invalid C++14 code with initialized lambda
                    capture: tree check: expected class ‘type’, have
                    ‘exceptional’ (error_mark) in add_capture, at
                    cp/lambda.c:505
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu
  Target Milestone: ---

This is a regression from 6.1.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/7.0.0/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 7.0.0 20160802 (experimental) [trunk revision 238983] (GCC)
$
$ g++-trunk -c -std=c++14 small.cpp
small.cpp: In function ‘void foo()’:
small.cpp:4:7: error: direct-list-initialization of ‘auto’ requires exactly one
element [-fpermissive]
   [n {}] {};
       ^
small.cpp:4:7: note: for deduction to ‘std::initializer_list’, use
copy-list-initialization (i.e. add ‘=’ before the ‘{’)
small.cpp:4:7: error: deducing from brace-enclosed initializer list requires
#include <initializer_list>
small.cpp:4:7: internal compiler error: tree check: expected class ‘type’, have
‘exceptional’ (error_mark) in add_capture, at cp/lambda.c:505
0x1071a07 tree_class_check_failed(tree_node const*, tree_code_class, char
const*, int, char const*)
        ../../gcc-source-trunk/gcc/tree.c:9793
0x8a32d4 tree_class_check
        ../../gcc-source-trunk/gcc/tree.h:3146
0x8a32d4 add_capture(tree_node*, tree_node*, tree_node*, bool, bool)
        ../../gcc-source-trunk/gcc/cp/lambda.c:505
0x7946cb cp_parser_lambda_introducer
        ../../gcc-source-trunk/gcc/cp/parser.c:10025
0x7946cb cp_parser_lambda_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:9733
0x795f6c cp_parser_primary_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:4960
0x797fe6 cp_parser_postfix_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:6717
0x7a101c cp_parser_unary_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:8012
0x7a1877 cp_parser_cast_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:8689
0x7a1e75 cp_parser_binary_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:8791
0x7a2760 cp_parser_assignment_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:9079
0x7a5059 cp_parser_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:9246
0x7a57cf cp_parser_expression_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:10709
0x7935fb cp_parser_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:10560
0x7942bc cp_parser_statement_seq_opt
        ../../gcc-source-trunk/gcc/cp/parser.c:10832
0x7943af cp_parser_compound_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:10786
0x7b2c4f cp_parser_function_body
        ../../gcc-source-trunk/gcc/cp/parser.c:20743
0x7b2c4f cp_parser_ctor_initializer_opt_and_function_body
        ../../gcc-source-trunk/gcc/cp/parser.c:20779
0x7b36f1 cp_parser_function_definition_after_declarator
        ../../gcc-source-trunk/gcc/cp/parser.c:25475
0x7b4405 cp_parser_function_definition_from_specifiers_and_declarator
        ../../gcc-source-trunk/gcc/cp/parser.c:25387
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 ()
{ 
  // should be e.g.: [n {0}] {};
  [n {}] {};
}