[PATCH update for 4.15 1/3] selftests: lib.mk: Introduce OVERRIDE_TARGETS

Introduce OVERRIDE_TARGETS to allow tests to express dependencies on
header files and .so, which require to override the selftests lib.mk
targets.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers-vg+e7yoeK/dWk0Htik3J/w@public.gmane.org>
CC: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
CC: Catalin Marinas <redacted>
CC: Will Deacon <redacted>
CC: Thomas Gleixner <redacted>
CC: Paul Turner <redacted>
CC: Andrew Hunter <redacted>
CC: Peter Zijlstra <redacted>
CC: Andy Lutomirski <redacted>
CC: Andi Kleen <andi-Vw/NltI1exuRpAAqCnN02g@public.gmane.org>
CC: Dave Watson <redacted>
CC: Chris Lameter <redacted>
CC: Ingo Molnar <redacted>
CC: "H. Peter Anvin" <redacted>
CC: Ben Maurer <redacted>
CC: Steven Rostedt <redacted>
CC: "Paul E. McKenney" <redacted>
CC: Josh Triplett <redacted>
CC: Linus Torvalds <torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
CC: Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
CC: Boqun Feng <redacted>
CC: Shuah Khan <redacted>
CC: linux-kselftest-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
CC: linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
---
 tools/testing/selftests/lib.mk | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
index 5bef05d6ba39..441d7bc63bb7 100644
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk

@@ -105,6 +105,9 @@ COMPILE.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c
 LINK.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH)
 endif
 
+# Selftest makefiles can override those targets by setting
+# OVERRIDE_TARGETS = 1.
+ifeq ($(OVERRIDE_TARGETS),)
 $(OUTPUT)/%:%.c
 	$(LINK.c) $^ $(LDLIBS) -o $@
 

@@ -113,5 +116,6 @@ $(OUTPUT)/%.o:%.S
 
 $(OUTPUT)/%:%.S
 	$(LINK.S) $^ $(LDLIBS) -o $@
+endif
 
 .PHONY: run_tests all clean install emit_tests

-- 
2.11.0