[Bug c/94968] New: [10 Regression] internal compiler error: tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.c:87

["anbu1024.me at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94968

            Bug ID: 94968
           Summary: [10 Regression] internal compiler error: tree check:
                    expected class ‘type’, have ‘exceptional’ (error_mark)
                    in useless_type_conversion_p, at gimple-expr.c:87
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: anbu1024.me at gmail dot com
  Target Milestone: ---

$ cat test.c 

int foo() { 
        __builtin_speculation_safe_value ( 1 , x );
}

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

$ gcc-10 --version
gcc (GCC) 10.0.1 20200419 (experimental)
Copyright (C) 2020 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

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

$ gcc-10 test.c 
test.c: In function ‘foo’:
test.c:3:41: error: ‘x’ undeclared (first use in this function)
    3 |  __builtin_speculation_safe_value ( 1 , x );
      |                                         ^
test.c:3:41: note: each undeclared identifier is reported only once for each
function it appears in
test.c:3:2: internal compiler error: tree check: expected class ‘type’, have
‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.c:87
    3 |  __builtin_speculation_safe_value ( 1 , x );
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
0x731f2f tree_class_check_failed(tree_node const*, tree_code_class, char
const*, int, char const*)
        ../../gcc-10-20200419/gcc/tree.c:9777
0x665cf0 tree_class_check(tree_node*, tree_code_class, char const*, int, char
const*)
        ../../gcc-10-20200419/gcc/tree.h:3410
0x665cf0 useless_type_conversion_p(tree_node*, tree_node*)
        ../../gcc-10-20200419/gcc/gimple-expr.c:87
0x8919e4 speculation_safe_value_resolve_params
        ../../gcc-10-20200419/gcc/c-family/c-common.c:6720
0x8919e4 resolve_overloaded_builtin(unsigned int, tree_node*, vec<tree_node*,
va_gc, vl_embed>*)
        ../../gcc-10-20200419/gcc/c-family/c-common.c:7407
0x81a6c9 c_build_function_call_vec(unsigned int, vec<unsigned int, va_heap,
vl_ptr>, tree_node*, vec<tree_node*, va_gc, vl_embed>*, vec<tree_node*, va_gc,
vl_embed>*)
        ../../gcc-10-20200419/gcc/c/c-typeck.c:3199
0x838cde c_parser_postfix_expression_after_primary
        ../../gcc-10-20200419/gcc/c/c-parser.c:10501
0x8307a1 c_parser_postfix_expression
        ../../gcc-10-20200419/gcc/c/c-parser.c:10176
0x834ada c_parser_unary_expression
        ../../gcc-10-20200419/gcc/c/c-parser.c:8273
0x83632d c_parser_cast_expression
        ../../gcc-10-20200419/gcc/c/c-parser.c:8115
0x8365b9 c_parser_binary_expression
        ../../gcc-10-20200419/gcc/c/c-parser.c:7918
0x837595 c_parser_conditional_expression
        ../../gcc-10-20200419/gcc/c/c-parser.c:7652
0x837bb0 c_parser_expr_no_commas
        ../../gcc-10-20200419/gcc/c/c-parser.c:7569
0x837e11 c_parser_expression
        ../../gcc-10-20200419/gcc/c/c-parser.c:10637
0x8385b7 c_parser_expression_conv
        ../../gcc-10-20200419/gcc/c/c-parser.c:10670
0x82dd0b c_parser_statement_after_labels
        ../../gcc-10-20200419/gcc/c/c-parser.c:6301
0x82ff71 c_parser_compound_statement_nostart
        ../../gcc-10-20200419/gcc/c/c-parser.c:5805
0x84c8c4 c_parser_compound_statement
        ../../gcc-10-20200419/gcc/c/c-parser.c:5617
0x84e381 c_parser_declaration_or_fndef
        ../../gcc-10-20200419/gcc/c/c-parser.c:2505
0x8566e3 c_parser_external_declaration
        ../../gcc-10-20200419/gcc/c/c-parser.c:1745
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

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

$ gcc-9 --version
gcc (GCC) 9.3.1 20200425
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

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

$ gcc-9 test.c 
test.c: In function ‘foo’:
test.c:3:41: error: ‘x’ undeclared (first use in this function)
    3 |  __builtin_speculation_safe_value ( 1 , x );
      |                                         ^
test.c:3:41: note: each undeclared identifier is reported only once for each
function it appears in
test.c:3:2: error: both arguments must be compatible
    3 |  __builtin_speculation_safe_value ( 1 , x );
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~