[Bug c++/89218] New: [8/9 Regression] g++ miscompiles functions returning non-void without return statements

[ldv at sourceware dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89218

            Bug ID: 89218
           Summary: [8/9 Regression] g++ miscompiles functions returning
                    non-void without return statements
           Product: gcc
           Version: 8.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ldv at sourceware dot org
  Target Milestone: ---

$ gcc -xc++ -S -O - <<EOF
static int foo() {}
int main() { return foo(); }
EOF
<stdin>: In function 'int foo()':
<stdin>:1:19: warning: no return statement in function returning non-void
[-Wreturn-type]

Results to

main:
.LFB1:
        .cfi_startproc
        .cfi_endproc

Executing this results to segfault.
Miscompilation happens with -Og and higher optimization levels.
gcc -xc is fine.