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From: "eggert at cs dot ucla.edu" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug analyzer/101713] -Wanalyzer-malloc-leak false positive with GNU
 coreutils hash table code
Date: Wed, 17 Nov 2021 20:28:47 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101713

--- Comment #2 from eggert at cs dot ucla.edu ---
(In reply to David Malcolm from comment #1)

> Am I right in thinking that there's a cast somewhere inside the hash table
> code that at some point casts away the const from the pointer and frees i=
t?

Yes there's a cast to void *, but no it doesn't free the storage. Instead, =
the
caller later is supposed to take ownership of the storage if it removes the
item from the hashtable, e.g., the caller can later do this:

   void *entry =3D hash_remove (pattern);
   free (entry);

where ENTRY will be the same pointer as STR in the sample code I gave earli=
er.
This means there's no leak in addpat per se.=