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Date: Wed, 10 Nov 2021 00:02:10 +0000
From: Joseph Myers <joseph@codesourcery.com>
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To: Xi Ruoyao <xry111@mengyan1223.wang>
CC: <gcc-patches@gcc.gnu.org>, Bruce Korb <bkorb@gnu.org>
Subject: Re: [PATCH] fixincludes: don't assume getcwd() can handle NULL
 argument
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On Tue, 9 Nov 2021, Xi Ruoyao via Gcc-patches wrote:

> POSIX says:
> 
>     On some implementations, if buf is a null pointer, getcwd() may obtain
>     size bytes of memory using malloc(). In this case, the pointer returned
>     by getcwd() may be used as the argument in a subsequent call to free().
>     Invoking getcwd() with buf as a null pointer is not recommended in
>     conforming applications.
> 
> This produces an error building GCC with --enable-werror-always:
> 
>     ../../../fixincludes/fixincl.c: In function ‘process’:
>     ../../../fixincludes/fixincl.c:1356:7: error: argument 1 is null but
>     the corresponding size argument 2 value is 4096 [-Werror=nonnull]

Isn't this warning actually a glibc bug 
<https://sourceware.org/bugzilla/show_bug.cgi?id=27476>?

-- 
Joseph S. Myers
joseph@codesourcery.com