coreutils-8.31.90-cc4c.tar.xz and LD_PRELOAD

[Bruno Haible]

On FreeBSD 12.0, NetBSD 9.0, OpenBSD 6.5, "make check" reports a couple
of skipped tests:

no-ctx.sh: skipped test: $CC -shared ... failed to build a shared lib
r-root.sh: skipped test: $CC -shared ... failed to build a shared lib
rm-readdir-fail.sh: skipped test: $CC -shared ... failed to build a shared lib
csplit-io-err.sh: skipped test: $CC -shared ... failed to build a shared lib
nfs-removal-race.sh: skipped test: $CC -shared ... failed to build a shared lib
no-mtab-status.sh: skipped test: $CC -shared ... failed to build a shared lib
skip-duplicates.sh: skipped test: $CC -shared ... failed to build a shared lib
getxattr-speedup.sh: skipped test: $CC -shared ... failed to build a shared lib

The prereq check tests not only whether a shared library can be built, but
also whether linking it with -ldl works.

However, on the following platforms, the dlopen() etc. functions exist in libc,
and a libdl does not exist:
  macOS, FreeBSD, NetBSD, OpenBSD, IRIX, OSF/1, Cygwin, Haiku.

The attached patch removes the requirement of a libdl. It enables 4 more tests
to be executed on FreeBSD, and produces no additional test failures on
FreeBSD, NetBSD, OpenBSD.

Output on FreeBSD 12.0:

no-ctx.sh: skipped test: this system lacks SELinux support
SKIP: tests/cp/no-ctx.sh
PASS: tests/rm/r-root.sh
PASS: tests/rm/rm-readdir-fail.sh
PASS: tests/misc/csplit-io-err.sh
nfs-removal-race.sh: skipped test: LD_PRELOAD was ineffective?
SKIP: tests/cp/nfs-removal-race.sh
no-mtab-status.sh: skipped test: no mntent.h available to confirm the interface
SKIP: tests/df/no-mtab-status.sh
skip-duplicates.sh: skipped test: no mntent.h available to confirm the interface
SKIP: tests/df/skip-duplicates.sh
PASS: tests/ls/getxattr-speedup.sh

Output on NetBSD 9.0:

no-ctx.sh: skipped test: this system lacks SELinux support
SKIP: tests/cp/no-ctx.sh
r-root.sh: skipped test: internal test failure: maybe LD_PRELOAD or gdb doesn't 
work?
SKIP: tests/rm/r-root.sh
rm-readdir-fail.sh: skipped test: internal test failure: maybe LD_PRELOAD 
doesn't work?
SKIP: tests/rm/rm-readdir-fail.sh
csplit-io-err.sh: skipped test: LD_PRELOAD interception failed
SKIP: tests/misc/csplit-io-err.sh
nfs-removal-race.sh: skipped test: LD_PRELOAD was ineffective?
SKIP: tests/cp/nfs-removal-race.sh
no-mtab-status.sh: skipped test: no mntent.h available to confirm the interface
SKIP: tests/df/no-mtab-status.sh
skip-duplicates.sh: skipped test: no mntent.h available to confirm the interface
SKIP: tests/df/skip-duplicates.sh
getxattr-speedup.sh: skipped test: internal test failure: maybe LD_PRELOAD 
doesn't work?
SKIP: tests/ls/getxattr-speedup.sh

Output on OpenBSD 6.5:

no-ctx.sh: skipped test: this system lacks SELinux support
SKIP: tests/cp/no-ctx.sh
r-root.sh: skipped test: internal test failure: maybe LD_PRELOAD or gdb doesn't 
work?
SKIP: tests/rm/r-root.sh
rm-readdir-fail.sh: skipped test: internal test failure: maybe LD_PRELOAD 
doesn't work?
SKIP: tests/rm/rm-readdir-fail.sh
csplit-io-err.sh: skipped test: /dev/full is required
SKIP: tests/misc/csplit-io-err.sh
nfs-removal-race.sh: skipped test: LD_PRELOAD was ineffective?
SKIP: tests/cp/nfs-removal-race.sh
no-mtab-status.sh: skipped test: no mntent.h available to confirm the interface
SKIP: tests/df/no-mtab-status.sh
skip-duplicates.sh: skipped test: no mntent.h available to confirm the interface
SKIP: tests/df/skip-duplicates.sh
getxattr-speedup.sh: skipped test: internal test failure: maybe LD_PRELOAD 
doesn't work?
SKIP: tests/ls/getxattr-speedup.sh

0001-tests-Enable-4-more-tests-to-be-executed-on-FreeBSD.patch
Description: Text Data