linux/tools/lib
Vitaly Chikunov 6d6c4c1bb5 tools lib: Fix builds when glibc contains strlcpy()
commit 6c4798d3f0 upstream.

Disable a couple of compilation warnings (which are treated as errors)
on strlcpy() definition and declaration, allowing users to compile perf
and kernel (objtool) when:

1. glibc have strlcpy() (such as in ALT Linux since 2004) objtool and
   perf build fails with this (in gcc):

  In file included from exec-cmd.c:3:
  tools/include/linux/string.h:20:15: error: redundant redeclaration of ‘strlcpy’ [-Werror=redundant-decls]
     20 | extern size_t strlcpy(char *dest, const char *src, size_t size);

2. clang ignores `-Wredundant-decls', but produces another warning when
   building perf:

    CC       util/string.o
  ../lib/string.c:99:8: error: attribute declaration must precede definition [-Werror,-Wignored-attributes]
  size_t __weak strlcpy(char *dest, const char *src, size_t size)
  ../../tools/include/linux/compiler.h:66:34: note: expanded from macro '__weak'
  # define __weak                 __attribute__((weak))
  /usr/include/bits/string_fortified.h:151:8: note: previous definition is here
  __NTH (strlcpy (char *__restrict __dest, const char *__restrict __src,

Committer notes:

The

 #pragma GCC diagnostic

directive was introduced in gcc 4.6, so check for that as well.

Fixes: ce99091 ("perf tools: Move strlcpy() from perf to tools/lib/string.c")
Fixes: 0215d59 ("tools lib: Reinstate strlcpy() header guard with __UCLIBC__")
Resolves: https://bugzilla.kernel.org/show_bug.cgi?id=118481
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Reviewed-by: Dmitry Levin <ldv@altlinux.org>
Cc: Dmitry Levin <ldv@altlinux.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: kbuild test robot <lkp@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Cc: Vineet Gupta <vineet.gupta1@synopsys.com>
Link: http://lore.kernel.org/lkml/20191224172029.19690-1-vt@altlinux.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-05 14:43:34 +00:00
..
api perf tools: Fix tracing_path_mount proper path 2018-10-16 12:27:46 -03:00
bpf libbpf: Fix error handling in bpf_map__reuse_fd() 2019-12-31 16:35:33 +01:00
lockdep tools lib traceevent, tools lib lockdep: Rename 'enum pevent_errno' to 'enum tep_errno' 2018-08-13 15:23:07 -03:00
subcmd libsubcmd: Use -O0 with DEBUG=1 2019-12-31 16:35:47 +01:00
symbol tools lib symbols: Introduce kallsyms__is_function() 2018-04-26 13:47:14 -03:00
traceevent libtraceevent: Fix lib installation with O= 2020-01-12 12:17:06 +01:00
bitmap.c
find_bit.c lib: optimize cpumask_next_and() 2018-02-06 18:32:44 -08:00
hweight.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rbtree.c
str_error_r.c objtool, perf: Fix GCC 8 -Wrestrict error 2018-03-19 13:51:54 -03:00
string.c tools lib: Fix builds when glibc contains strlcpy() 2020-02-05 14:43:34 +00:00
vsprintf.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00