linux/tools
Fathi Boudra 7d4e591bc0 selftests: timers: use LDLIBS instead of LDFLAGS
posix_timers fails to build due to undefined reference errors:

 aarch64-linaro-linux-gcc --sysroot=/build/tmp-rpb-glibc/sysroots/hikey
 -O2 -pipe -g -feliminate-unused-debug-types -O3 -Wl,-no-as-needed -Wall
 -DKTEST  -Wl,-O1 -Wl,--hash-style=gnu -Wl,--as-needed -lrt -lpthread
 posix_timers.c
 -o /build/tmp-rpb-glibc/work/hikey-linaro-linux/kselftests/4.12-r0/linux-4.12-rc7/tools/testing/selftests/timers/posix_timers
 /tmp/cc1FTZzT.o: In function `check_timer_create':
 /usr/src/debug/kselftests/4.12-r0/linux-4.12-rc7/tools/testing/selftests/timers/posix_timers.c:157:
 undefined reference to `timer_create'
 /usr/src/debug/kselftests/4.12-r0/linux-4.12-rc7/tools/testing/selftests/timers/posix_timers.c:170:
 undefined reference to `timer_settime'
 collect2: error: ld returned 1 exit status

It's GNU Make and linker specific.

The default Makefile rule looks like:

$(CC) $(CFLAGS) $(LDFLAGS) $@ $^ $(LDLIBS)

When linking is done by gcc itself, no issue, but when it needs to be passed
to proper ld, only LDLIBS follows and then ld cannot know what libs to link
with.

More detail:
https://www.gnu.org/software/make/manual/html_node/Implicit-Variables.html

LDFLAGS
Extra flags to give to compilers when they are supposed to invoke the linker,
‘ld’, such as -L. Libraries (-lfoo) should be added to the LDLIBS variable
instead.

LDLIBS
Library flags or names given to compilers when they are supposed to invoke the
linker, ‘ld’. LOADLIBES is a deprecated (but still supported) alternative to
LDLIBS. Non-library linker flags, such as -L, should go in the LDFLAGS
variable.

https://lkml.org/lkml/2010/2/10/362

tools/perf: libraries must come after objects

Link order matters, use LDLIBS instead of LDFLAGS to properly link against
libpthread.

Signed-off-by: Denys Dmytriyenko <denys@ti.com>
Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
Signed-off-by: Shuah Khan <shuah@kernel.org>
2019-01-28 08:02:12 -07:00
..
accounting delayacct: track delays from thrashing cache pages 2018-10-26 16:26:32 -07:00
arch jump_label: move 'asm goto' support test to Kconfig 2019-01-06 09:46:51 +09:00
bpf tools: bpftool: do not force gcc as CC 2018-12-19 21:57:25 +01:00
build perf build: Don't unconditionally link the libbfd feature test to -liberty and -lz 2018-12-21 09:42:46 -03:00
cgroup
crypto crypto: user - rename err_cnt parameter 2018-12-07 14:15:00 +08:00
firewire
firmware tools: Add 'firmware' category and add ihex2fw tool 2018-11-11 12:58:27 -08:00
gpio tools gpio: Allow overriding CFLAGS 2018-12-28 16:33:08 -03:00
hv Tools: hv: kvp: Fix a warning of buffer overflow with gcc 8.0.1 2018-11-11 12:58:27 -08:00
iio
include Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-01-06 16:30:14 -08:00
kvm/kvm_stat tools/kvm_stat: switch to python3 2018-11-27 12:53:44 +01:00
laptop
leds
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-12-27 13:04:52 -08:00
memory-model
nfsd
objtool objtool: Fix segfault in .cold detection with -ffunction-sections 2018-11-20 18:59:00 +01:00
pci
pcmcia
perf Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-01-06 16:30:14 -08:00
power perf/core improvements and fixes: 2019-01-03 14:05:16 +01:00
scripts
spi
testing selftests: timers: use LDLIBS instead of LDFLAGS 2019-01-28 08:02:12 -07:00
thermal/tmon tools thermal tmon: Allow overriding CFLAGS assignments 2018-12-28 16:33:08 -03:00
time
usb
virtio virtio: fix test build after uio.h change 2018-12-19 18:23:49 -05:00
vm tools/vm/page-types.c: fix "kpagecount returned fewer pages than expected" failures 2018-12-28 12:11:50 -08:00
wmi
Makefile tools: Add 'firmware' category and add ihex2fw tool 2018-11-11 12:58:27 -08:00