[Bug c++/77556] New: ICE on invalid C++ code with non-constant non-type template argument: in convert_nontype_argument, at cp/pt.c:6416

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77556

            Bug ID: 77556
           Summary: ICE on invalid C++ code with non-constant non-type
                    template argument: in convert_nontype_argument, at
                    cp/pt.c:6416
           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: ---

It also affects 6.x and is a regression from 5.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 20160910 (experimental) [trunk revision 240069] (GCC)
$
$ g++-trunk -c small.cpp
small.cpp: In function ‘void f()’:
small.cpp:5:40: internal compiler error: in convert_nontype_argument, at
cp/pt.c:6416
  L1: L2: A < (long) &&L2 - (long) &&L1 > a;
                                        ^
0x6f1717 convert_nontype_argument
        ../../gcc-source-trunk/gcc/cp/pt.c:6416
0x6f8323 convert_template_argument
        ../../gcc-source-trunk/gcc/cp/pt.c:7285
0x7039f3 coerce_template_parms
        ../../gcc-source-trunk/gcc/cp/pt.c:7747
0x70592a lookup_template_class_1
        ../../gcc-source-trunk/gcc/cp/pt.c:8320
0x70592a lookup_template_class(tree_node*, tree_node*, tree_node*, tree_node*,
int, int)
        ../../gcc-source-trunk/gcc/cp/pt.c:8663
0x8238bd finish_template_type(tree_node*, tree_node*, int)
        ../../gcc-source-trunk/gcc/cp/semantics.c:3140
0x7ab894 cp_parser_template_id
        ../../gcc-source-trunk/gcc/cp/parser.c:15049
0x7abb3a cp_parser_class_name
        ../../gcc-source-trunk/gcc/cp/parser.c:21354
0x79d1ed cp_parser_qualifying_entity
        ../../gcc-source-trunk/gcc/cp/parser.c:6278
0x79d1ed cp_parser_nested_name_specifier_opt
        ../../gcc-source-trunk/gcc/cp/parser.c:5962
0x79b32d cp_parser_simple_type_specifier
        ../../gcc-source-trunk/gcc/cp/parser.c:16372
0x798891 cp_parser_type_specifier
        ../../gcc-source-trunk/gcc/cp/parser.c:16049
0x7ac253 cp_parser_decl_specifier_seq
        ../../gcc-source-trunk/gcc/cp/parser.c:12889
0x7b94a1 cp_parser_simple_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:12416
0x7b9921 cp_parser_block_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:12363
0x7ba378 cp_parser_declaration_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:11975
0x7b6d0b cp_parser_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:10581
0x7b783c cp_parser_statement_seq_opt
        ../../gcc-source-trunk/gcc/cp/parser.c:10859
0x7b792f cp_parser_compound_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:10813
0x7b7adf cp_parser_function_body
        ../../gcc-source-trunk/gcc/cp/parser.c:20832
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.
$


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


template < int > struct A {};

void f ()
{
 L1: L2: A < (long) &&L2 - (long) &&L1 > a;
}