Example: provenance_basic_using_uintptr_t_auto_yx.c

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    #include <stdio.h>
    #include <string.h> 
    #include <stdint.h>
    #include <inttypes.h>
    int main() {
      int y=2, x=1;
      uintptr_t ux = (uintptr_t)&x;
      uintptr_t uy = (uintptr_t)&y;
      uintptr_t offset = 4;
      ux = ux + offset;
      int *p = (int *)ux; // does this have undefined behaviour?
      int *q = &y;
      printf("Addresses: &x=%p p=%p &y=%"PRIxPTR\
             "\n",(void*)&x,(void*)p,(unsigned long)uy);
      if (memcmp(&p, &q, sizeof(p)) == 0) {
        *p = 11; // does this have undefined behaviour?
        printf("x=%d  y=%d  *p=%d  *q=%d\n",x,y,*p,*q); 
      }
    }
[link to run test in Cerberus]

Experimental data (what does this mean?) 



cerberus-concrete-PVI-plain Addresses: &x=(@72, 0xffffedcc) p=(@71, 0xffffedd0) &y=ffffedd0
x=1  y=11  *p=11  *q=11


cerberus-concrete-PVI-ae Addresses: &x=(@72, 0xffffedcc) p=(@71, 0xffffedd0) &y=ffffedd0
x=1  y=11  *p=11  *q=11


cerberus-concrete-PVI-ae-udi Addresses: &x=(@72, 0xffffedcc) p=(@iota(0), 0xffffedd0) &y=ffffedd0
x=1  y=11  *p=11  *q=11


gcc-8.3-O0 Addresses: &x=0x7ffeefbff2e0 p=0x7ffeefbff2e4 &y=7ffeefbff2e4
x=1  y=11  *p=11  *q=11


gcc-8.3-O2 Addresses: &x=0x7ffeefbff2ec p=0x7ffeefbff2f0 &y=7ffeefbff2e8


gcc-8.3-O3 Addresses: &x=0x7ffeefbff2ec p=0x7ffeefbff2f0 &y=7ffeefbff2e8


gcc-8.3-O2-no-strict-aliasing Addresses: &x=0x7ffeefbff2ac p=0x7ffeefbff2b0 &y=7ffeefbff2a8


gcc-8.3-O3-no-strict-aliasing Addresses: &x=0x7ffeefbff2ac p=0x7ffeefbff2b0 &y=7ffeefbff2a8


clang-7.0.1-O0 Addresses: &x=0x7ffeefbff2e4 p=0x7ffeefbff2e8 &y=7ffeefbff2e8
x=1  y=11  *p=11  *q=11


clang-7.0.1-O2 Addresses: &x=0x7ffeefbff2dc p=0x7ffeefbff2e0 &y=7ffeefbff2d8


clang-7.0.1-O3 Addresses: &x=0x7ffeefbff2dc p=0x7ffeefbff2e0 &y=7ffeefbff2d8


clang-7.0.1-O2-no-strict-aliasing Addresses: &x=0x7ffeefbff29c p=0x7ffeefbff2a0 &y=7ffeefbff298


clang-7.0.1-O3-no-strict-aliasing Addresses: &x=0x7ffeefbff29c p=0x7ffeefbff2a0 &y=7ffeefbff298


icc-19-O0 Addresses: &x=0x7fffffffe684 p=0x7fffffffe688 &y=7fffffffe680


icc-19-O2 Addresses: &x=0x6046c0 p=0x6046c4 &y=6046c4
x=1  y=2  *p=11  *q=11


icc-19-O3 Addresses: &x=0x6046c0 p=0x6046c4 &y=6046c4
x=1  y=2  *p=11  *q=11


icc-19-O2-no-strict-aliasing Addresses: &x=0x6046c0 p=0x6046c4 &y=6046c4
x=1  y=2  *p=11  *q=11


icc-19-O3-no-strict-aliasing Addresses: &x=0x6046c0 p=0x6046c4 &y=6046c4
x=1  y=2  *p=11  *q=11