| 
  
 test_1 
  | 
     ‘test_1’: events 1-3 
|     8 |   void *ptr = malloc (1024); |  
 |               ^~~~~~~~~~~~~ |  
 |               | |  
 |               (1) allocated here |  
|     9 |   free (ptr); |  
 |   ~~~~~~~~~~    |  
 |   | |  
 |   (2) first ‘free’ here |  
|    10 |   free (ptr); /* { dg-warning "double-'free' of 'ptr'"  } */ |  
 |   ~~~~~~~~~~    |  
 |   | |  
 |   (3) second ‘free’ here; first ‘free’ was at (2) |  
 
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