[Bug sanitizer/126287] New: ICE with counted_by and bitfields

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126287

            Bug ID: 126287
           Summary: ICE with counted_by and bitfields
           Product: gcc
           Version: 16.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: sanitizer
          Assignee: unassigned at gcc dot gnu.org
          Reporter: uecker at gcc dot gnu.org
                CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
                    jakub at gcc dot gnu.org, kcc at gcc dot gnu.org
  Target Milestone: ---

The following code ICEs with -fsanitize=bounds.

struct foo {
#if 1
    unsigned int FLOAT : 1;
    unsigned int INT : 1;
#else
    // this works
    bool FLOAT;
    bool INT;
#endif
    union { 
        float a[] __attribute__((counted_by(FLOAT)));
        int b[] __attribute__((counted_by(INT)));
    };
};



int main()
{
    struct foo x = { .FLOAT = 1 };
    printf("%d\n", x.FLOAT);
    x.a[0] = 1.;
    printf("%d\n", x.INT);
    x.b[0] = 1; // BOUNDS
}