Example: provenance_roundtrip_via_intptr_t.c

up: index
prev: provenance_equality_global_fn_yx.c
next: provenance_basic_using_uintptr_t_global_xy.c

1
2
3
4
5
6
7
8
9
10

    #include <stdio.h>
    #include <inttypes.h>
    int x=1;
    int main() {
      int *p = &x;
      intptr_t i = (intptr_t)p;
      int *q = (int *)i;
      *q = 11; // is this free of undefined behaviour?
      printf("*p=%d  *q=%d\n",*p,*q);  
    }
[link to run test in Cerberus]

Experimental data (what does this mean?) 



cerberus-concrete-PVI *p=11  *q=11


cerberus-concrete-PNVI *p=11  *q=11


gcc-8.1-O0 *p=11  *q=11


gcc-8.1-O2 *p=11  *q=11


gcc-8.1-O3 *p=11  *q=11


gcc-8.1-O2-no-strict-aliasing *p=11  *q=11


gcc-8.1-O3-no-strict-aliasing *p=11  *q=11


clang-6.0-O0 *p=11  *q=11


clang-6.0-O2 *p=11  *q=11


clang-6.0-O3 *p=11  *q=11


clang-6.0-O2-no-strict-aliasing *p=11  *q=11


clang-6.0-O3-no-strict-aliasing *p=11  *q=11


clang-6.0-UBSAN *p=11  *q=11


clang-6.0-ASAN *p=11  *q=11


clang-6.0-MSAN *p=11  *q=11


icc-19-O0 *p=11  *q=11


icc-19-O2 *p=11  *q=11


icc-19-O3 *p=11  *q=11


icc-19-O2-no-strict-aliasing *p=11  *q=11


icc-19-O3-no-strict-aliasing *p=11  *q=11


compcert-3.4 *p=11  *q=11


compcert-3.4-O *p=11  *q=11


kcc-1.0 *p=11  *q=11
Conversion from an integer to non-null pointer:
      > in main at provenance_roundtrip_via_intptr_t.c:7:3

    Implementation defined behavior (IMPL-CCV13):
        see C11 section 6.3.2.3:5 http://rvdoc.org/C11/6.3.2.3
        see CERT section INT36-C http://rvdoc.org/CERT/INT36-C