lkml.org 
[lkml]   [2022]   [Jan]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: linux-next 20220125 - build failure in objtool with gcc 12
On Wed, Jan 26, 2022 at 4:57 PM Valdis Klētnieks
<valdis.kletnieks@vt.edu> wrote:
>
> Fedora Rawhide shipped gcc12, which apparently includes a new warning that
> causes a build failure. Apparently, it's unable to figure out that 'ptr' remains
> valid on failed realloc(), and we only call realloc() again on failures...

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104069 explains (toward
the end) why gcc is leaving it to be fixed in the kernel.


> CC /usr/src/linux-next/tools/objtool/exec-cmd.o
> CC /usr/src/linux-next/tools/objtool/help.o
> In file included from help.c:12:
> In function 'xrealloc',
> inlined from 'add_cmdname' at help.c:24:2:
> subcmd-util.h:56:23: error: pointer may be used after 'realloc' [-Werror=use-after-free]
> 56 | ret = realloc(ptr, size);
> | ^~~~~~~~~~~~~~~~~~
> subcmd-util.h:52:21: note: call to 'realloc' here
> 52 | void *ret = realloc(ptr, size);
> | ^~~~~~~~~~~~~~~~~~
> subcmd-util.h:58:31: error: pointer may be used after 'realloc' [-Werror=use-after-free]
> 58 | ret = realloc(ptr, 1);
> | ^~~~~~~~~~~~~~~
> subcmd-util.h:52:21: note: call to 'realloc' here
> 52 | void *ret = realloc(ptr, size);
> | ^~~~~~~~~~~~~~~~~~
> cc1: all warnings being treated as errors
> make[4]: *** [/usr/src/linux-next/tools/build/Makefile.build:97: /usr/src/linux-next/tools/objtool/help.o] Error 1
> make[3]: *** [Makefile:59: /usr/src/linux-next/tools/objtool/libsubcmd-in.o] Error 2
> make[2]: *** [Makefile:63: /usr/src/linux-next/tools/objtool/libsubcmd.a] Error 2
> make[1]: *** [Makefile:69: objtool] Error 2
> make: *** [Makefile:1405: tools/objtool] Error 2

\
 
 \ /
  Last update: 2022-01-27 16:35    [W:0.038 / U:0.468 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site