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      1 // RUN: %clang_cc1 -analyze -analyzer-checker=core,alpha.core -analyzer-store=region -analyzer-constraints=range -verify -fblocks %s
      2 
      3 // <rdar://problem/6776949>
      4 // main's 'argc' argument is always > 0
      5 int main(int argc, char* argv[]) {
      6   int *p = 0;
      7 
      8   if (argc == 0)
      9     *p = 1;
     10 
     11   if (argc == 1)
     12     return 1;
     13 
     14   int x = 1;
     15   int i;
     16   
     17   for(i=1;i<argc;i++){
     18     p = &x;
     19   }
     20 
     21   return *p; // no-warning
     22 }
     23 
     24 // PR 5969: the comparison of argc < 3 || argc > 4 should constraint the switch
     25 //  statement from having the 'default' branch taken.  This previously reported a false
     26 //  positive with the use of 'v'.
     27 
     28 int pr5969(int argc, char *argv[]) {
     29 
     30   int v;
     31 
     32   if ((argc < 3) || (argc > 4)) return 0;
     33 
     34   switch(argc) {
     35     case 3:
     36       v = 33;
     37       break;
     38     case 4:
     39       v = 44;
     40       break;
     41   }
     42 
     43   return v; // no-warning
     44 }
     45 
     46 int pr5969_positive(int argc, char *argv[]) {
     47 
     48   int v;
     49 
     50   if ((argc < 3) || (argc > 4)) return 0;
     51 
     52   switch(argc) {
     53     case 3:
     54       v = 33;
     55       break;
     56   }
     57 
     58   return v; // expected-warning{{Undefined or garbage value returned to caller}}
     59 }
     60