It also cleanups the multiple inclusion by leaving the ifunc
implementation to undef the weak_alias and libc_hidden_def.
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.
I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah. I don't
know why I run into these diagnostics whereas others evidently do not.
remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
Various code in glibc uses __strnlen instead of strnlen for namespace
reasons. However, __strnlen does not use libc_hidden_proto /
libc_hidden_def (as is normally done for any function defined and
called within the same library, whether or not exported from the
library and whatever namespace it is in), so the compiler does not
know that those calls are to a function within libc.
This patch uses libc_hidden_proto / libc_hidden_def with __strnlen.
On x86_64, it makes no difference to the installed stripped shared
libraries. On 32-bit x86, it causes __strnlen calls to go to the same
place as strnlen calls (the fallback strnlen implementation), rather
than through a PLT entry for the strnlen IFUNC; I'm not sure of the
logic behind when calls from within libc should use IFUNCs versus when
they should go direct to a particular function implementation, but
clearly it doesn't make sense for strnlen and __strnlen to be handled
differently in this regard.
Tested for x86_64 and x86 (testsuite, and comparison of installed
shared libraries as described above).
* string/strnlen.c [!STRNLEN] (__strnlen): Use libc_hidden_def.
* include/string.h (__strnlen): Use libc_hidden_proto.
* sysdeps/aarch64/strnlen.S (__strnlen): Use libc_hidden_def.
* sysdeps/i386/i686/multiarch/strnlen-c.c [SHARED]
(libc_hidden_def): Define __GI___strnlen as well as __GI_strnlen.
* sysdeps/powerpc/powerpc32/power4/multiarch/strnlen-power7.S
(libc_hidden_def): Undefine and redefine.
* sysdeps/powerpc/powerpc32/power4/multiarch/strnlen-ppc32.c
[SHARED] (libc_hidden_def): Define __GI___strnlen as well as
__GI_strnlen.
* sysdeps/powerpc/powerpc32/power7/strnlen.S (__strnlen): Use
libc_hidden_def.
* sysdeps/tile/tilegx/strnlen.c (__strnlen): Likewise.
