Example: provenance_equality_uintptr_t_auto_yx.c

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    #include <stdio.h>
    #include <inttypes.h> 
    int main() {
      int y=2, x=1;
      uintptr_t p = (uintptr_t)(&x + 1);
      uintptr_t q = (uintptr_t)&y;
      printf("Addresses: p=%" PRIxPTR " q=%" PRIxPTR "\n",
             p,q);
      _Bool b = (p==q);
      // can this be false even with identical addresses?
      printf("(p==q) = %s\n", b?"true":"false");
      return 0;
    }
[link to run test in Cerberus]

Experimental data (what does this mean?) 



cerberus-concrete-PVI Addresses: p=40 q=38
(p==q) = false


cerberus-concrete-PNVI Addresses: p=40 q=38
(p==q) = false


gcc-8.1-O0 Addresses: p=7fffffffe708 q=7fffffffe708
(p==q) = true


gcc-8.1-O2 Addresses: p=7fffffffe720 q=7fffffffe718
(p==q) = false


gcc-8.1-O3 Addresses: p=7fffffffe720 q=7fffffffe718
(p==q) = false


gcc-8.1-O2-no-strict-aliasing Addresses: p=7fffffffe700 q=7fffffffe6f8
(p==q) = false


gcc-8.1-O3-no-strict-aliasing Addresses: p=7fffffffe700 q=7fffffffe6f8
(p==q) = false


clang-6.0-O0 Addresses: p=7fffffffe718 q=7fffffffe718
(p==q) = true


clang-6.0-O2 Addresses: p=7fffffffe714 q=7fffffffe714
(p==q) = true


clang-6.0-O3 Addresses: p=7fffffffe714 q=7fffffffe714
(p==q) = true


clang-6.0-O2-no-strict-aliasing Addresses: p=7fffffffe6e4 q=7fffffffe6e4
(p==q) = true


clang-6.0-O3-no-strict-aliasing Addresses: p=7fffffffe6e4 q=7fffffffe6e4
(p==q) = true


clang-6.0-UBSAN Addresses: p=7fffffffe704 q=7fffffffe704
(p==q) = true


clang-6.0-ASAN Addresses: p=7fffffffe694 q=7fffffffe680
(p==q) = false


clang-6.0-MSAN Addresses: p=7fffffffe6e4 q=7fffffffe6e4
(p==q) = true


icc-19-O0 Addresses: p=7fffffffe6fc q=7fffffffe6f4
(p==q) = false


icc-19-O2 Addresses: p=6046c4 q=6046c4
(p==q) = true


icc-19-O3 Addresses: p=6046c4 q=6046c4
(p==q) = true


icc-19-O2-no-strict-aliasing Addresses: p=6046c4 q=6046c4
(p==q) = true


icc-19-O3-no-strict-aliasing Addresses: p=6046c4 q=6046c4
(p==q) = true


compcert-3.4 Addresses: p=7fffffffe6e0 q=7fffffffe6d8
(p==q) = false


compcert-3.4-O Addresses: p=7fffffffe6e0 q=7fffffffe6d8
(p==q) = false


kcc-1.0 Addresses: p=0 q=0
(p==q) = true
Printing an unspecified value:
      > in printf at provenance_equality_uintptr_t_auto_yx.c:7:3
        in main at provenance_equality_uintptr_t_auto_yx.c:7:3

    Unspecified value or behavior (USP-STDIO2):
        see C11 section 7.21.6.1:8 http://rvdoc.org/C11/7.21.6.1

Comparison of unspecified value:
      > in main at provenance_equality_uintptr_t_auto_yx.c:11:3

    Unspecified value or behavior (USP-CERL7):
        see C11 section 6.5.9 http://rvdoc.org/C11/6.5.9
        see MISRA-C section 8.1:3 http://rvdoc.org/MISRA-C/8.1