clang/test/Analysis/array-punned-region.c

   1 // RUN: %clang_analyze_cc1 -analyzer-checker=core,alpha.core,debug.ExprInspection -verify -analyzer-config eagerly-assume=false -triple x86_64-pc-linux-gnu %s
   2
   3 // RUN: %clang_analyze_cc1 -analyzer-checker=core,alpha.core,debug.ExprInspection -verify -analyzer-config eagerly-assume=false -triple i386-pc-linux-gnu  %s
   4
   5 int clang_analyzer_eval(int);
   6
   7 typedef struct {
   8   int a : 1;
   9   int b[2];
  10 } BITFIELD_CAST;
  11
  12 void array_struct_bitfield_1() {
  13   BITFIELD_CAST ff = {0};
  14   BITFIELD_CAST *pff = &ff;
  15   clang_analyzer_eval(*((int *)pff + 1) == 0); // expected-warning{{TRUE}}
  16   ff.b[0] = 3;
  17   clang_analyzer_eval(*((int *)pff + 1) == 3); // expected-warning{{TRUE}}
  18 }
  19
  20 int array_struct_bitfield_2() {
  21   BITFIELD_CAST ff = {0};
  22   BITFIELD_CAST *pff = &ff;
  23   int a = *((int *)pff + 2); // expected-warning{{Assigned value is garbage or undefined [core.uninitialized.Assign]}}
  24   return a;
  25 }
  26
  27 typedef struct {
  28   unsigned int a : 1;
  29   unsigned int x : 31;
  30   unsigned int c : 1;
  31   int b[2];
  32 } mystruct;
  33
  34 void array_struct_bitfield_3() {
  35   mystruct ff;
  36   mystruct *pff = &ff;
  37   ff.b[0] = 3;
  38   clang_analyzer_eval(*((int *)pff + 2) == 3); // expected-warning{{TRUE}}
  39 }