| 
  
 test_12 
  | 
     ‘test_12’: events 1-3 
|   124 |   void *ptr = malloc (1024); |  
 |               ^~~~~~~~~~~~~ |  
 |               | |  
 |               (1) allocated here |  
| [...] |  |  
|   128 |       free (ptr); |  
 |       ~~~~~~~~~~ |  
 |       | |  
 |       (2) first ‘free’ here |  
|   129 |       free (ptr); /* { dg-warning "double-'free' of 'ptr'" } */ |  
 |       ~~~~~~~~~~ |  
 |       | |  
 |       (3) second ‘free’ here; first ‘free’ was at (2) |  
 
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