[Bug c++/71665] ICE on invalid C++ code with non-integral constant enumerator value: in cxx_eval_constant_expression, at cp/constexpr.c:3918

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71665

Zhendong Su <su at cs dot ucdavis.edu> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|ICE on invalid C++ code     |ICE on invalid C++ code
                   |with non-integral constant  |with non-integral constant
                   |enumerator value:           |enumerator value: in
                   |                            |cxx_eval_constant_expressio
                   |                            |n, at cp/constexpr.c:3918

--- Comment #1 from Zhendong Su <su at cs dot ucdavis.edu> ---
The following C++ code causes an ICE when compiled with the current GCC trunk
on x86_64-linux-gnu in both 32-bit and 64-bit modes.  

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 20160625 (experimental) [trunk revision 237780] (GCC) 
$ 
$ g++-6.1 -c small.cpp
small.cpp:4:14: error: enumerator value for ‘a’ is not an integer constant
   enum { a = f };
              ^
$ 
$ g++-trunk -c small.cpp
small.cpp:4:14: internal compiler error: in cxx_eval_constant_expression, at
cp/constexpr.c:3918
   enum { a = f };
              ^
0x8acaed cxx_eval_constant_expression
        ../../gcc-source-trunk/gcc/cp/constexpr.c:3918
0x8b1929 cxx_eval_outermost_constant_expr
        ../../gcc-source-trunk/gcc/cp/constexpr.c:4211
0x6a22c7 build_enumerator(tree_node*, tree_node*, tree_node*, tree_node*,
unsigned int)
        ../../gcc-source-trunk/gcc/cp/decl.c:13588
0x7a98e2 cp_parser_enumerator_definition
        ../../gcc-source-trunk/gcc/cp/parser.c:17431
0x7a98e2 cp_parser_enumerator_list
        ../../gcc-source-trunk/gcc/cp/parser.c:17360
0x7a98e2 cp_parser_enum_specifier
        ../../gcc-source-trunk/gcc/cp/parser.c:17287
0x78aea9 cp_parser_type_specifier
        ../../gcc-source-trunk/gcc/cp/parser.c:15813
0x79fc23 cp_parser_decl_specifier_seq
        ../../gcc-source-trunk/gcc/cp/parser.c:12763
0x7af2ed cp_parser_member_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:22334
0x78b118 cp_parser_member_specification_opt
        ../../gcc-source-trunk/gcc/cp/parser.c:22186
0x78b118 cp_parser_class_specifier_1
        ../../gcc-source-trunk/gcc/cp/parser.c:21365
0x78b118 cp_parser_class_specifier
        ../../gcc-source-trunk/gcc/cp/parser.c:21601
0x78b118 cp_parser_type_specifier
        ../../gcc-source-trunk/gcc/cp/parser.c:15841
0x79fc23 cp_parser_decl_specifier_seq
        ../../gcc-source-trunk/gcc/cp/parser.c:12763
0x7ad111 cp_parser_simple_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:12304
0x7ad561 cp_parser_block_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:12251
0x7b6940 cp_parser_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:12148
0x7b5414 cp_parser_declaration_seq_opt
        ../../gcc-source-trunk/gcc/cp/parser.c:12027
0x7b5748 cp_parser_translation_unit
        ../../gcc-source-trunk/gcc/cp/parser.c:4329
0x7b5748 c_parse_file()
        ../../gcc-source-trunk/gcc/cp/parser.c:37491
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.
$ 


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


class A 
{
  int f ();
  enum { a = f };
};