It is automatically set when -fPIC is passed to the compiler.
Reviewed by: dim, kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D1179
This ensures strerror() and friends continue to work correctly even if a
(non-PIE) executable linked against an older libc imports sys_errlist (which
causes sys_errlist to refer to the executable's copy with a size fixed when
that executable was linked).
The executable's use of sys_errlist remains broken because it uses the
current value of sys_nerr and may access past the bounds of the array.
Different from the message "Using sys_errlist from executables is not
ABI-stable" on freebsd-arch, this change does not affect the static library.
There seems no reason to prevent overriding the error messages in the static
library.
Of course, strerror_r() may still fail with ERANGE.
Although the POSIX specification said this could fail with EINVAL and
doing this likely indicates invalid use of errno, most other
implementations permitted it, various POSIX testsuites require it to
work (matching the older sys_errlist array) and apparently some
applications depend on it.
PR: standards/151316
MFC after: 1 week
these at the moment, but applications that test for them will now
have a better chance of compiling.
I have intentionally omitted errnos that are only good for STREAMS,
since apps that use STREAMS won't compile anyway. The exception is
EPROTO, which was apparently intended for STREAMS, but worth having
anyway because Linux (mis)uses it for other things.
#define EDOFUS 88 /* Programming error */
This can be used to signal error situations which indicate that the
program logic or assumptions is deficient.
