[Bug tree-optimization/99235] New: Null pointer check incorrectly deleted for static pointer

[sebastianquilter at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99235

            Bug ID: 99235
           Summary: Null pointer check incorrectly deleted for static
                    pointer
           Product: gcc
           Version: 10.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: sebastianquilter at gmail dot com
  Target Milestone: ---

int main()
{
    static char* ptr = (char*)1;
    --ptr;
    if(ptr){
        return 1;
    }
    return 0;
}

Compiled with -O0, it returns 0
Compiled with -O1, it returns 1
Compiled with -O1 -fno-delete-null-pointer-checks, it returns 0