Bug path

test
‘test’: events 1-3
7 void *ptr = malloc(512);
^~~~~~~~~~~
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(1) allocated here
8 free(ptr);
~~~~~~~~~
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(2) first ‘free’ here
9 free(ptr); /* { dg-warning "double-'free'" "" { xfail *-*-* } } */
~~~~~~~~~
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(3) second ‘free’ here; first ‘free’ was at (2)