[Bug c/117747] ICE: tree check: expected class ‘type’, have ‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:86

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117747

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2024-11-25
     Ever confirmed|0                           |1
             Blocks|                            |101057
             Status|UNCONFIRMED                 |NEW
           Keywords|                            |error-recovery,
                   |                            |ice-on-invalid-code
            Version|unknown                     |15.0

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed also with -fgimple:

> ./cc1 -quiet t.c -fgimple
t.c: In function ‘foo’:
t.c:3:10: error: ‘b’ undeclared (first use in this function)
    3 | int t1 ; b = - 7 ;
      |          ^
t.c:3:10: note: each undeclared identifier is reported only once for each
function it appears in
t.c:4:1: internal compiler error: tree check: expected class ‘type’, have
‘exceptional’ (error_mark) in useless_type_conversion_p, at gimple-expr.cc:86
    4 | }
      | ^

the GIMPLE FE emits

<<< error >>> = -7;

note the GIMPLE FE isn't designed to handle all errors upfront, instead
it resorts to the verifier.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101057
[Bug 101057] [meta-bug] [gimplefe] GIMPLE frontend issues