Date: Tue, 21 Apr 2026 16:56:32 +0200 (CEST)
From: Henrik TJ <henrik@0x48.dk>
To: PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: Fix memory leak in postmasterMain
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Hi

On Sat, 21 Feb 2026, Henrik TJ wrote:

> This is fairly inconsequential as memory leaks goes, but if -D is used when 
> starting postgres, the memory allocated by stdrup() will never be freed. 
> Found with valgrind.

Rebased version of this patch attached.

To see valgrind catch the leak:

1. Compile with valgrind.
2. Run postgres with valgrind:
    valgrind --leak-check=full ./pgrun/bin/postgres -D pgdata/

The -D argument is required, as it is the argument from there that does 
not get freed. This should yield:

==444240== 8 bytes in 1 blocks are definitely lost in loss record 29 of 849
==444240==    at 0x4840B26: malloc (vg_replace_malloc.c:447)
==444240==    by 0x5114A2E: strdup (strdup.c:42)
==444240==    by 0x6B7CE0: PostmasterMain (../src/backend/postmaster/postmaster.c:656)
==444240==    by 0x602555: main (../src/backend/main/main.c:231)


   best regards, Henrik
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