[PATCH v3 bpf-next 09/14] samples: bpf: makefile: use own flags but not host when cross compile

[Ivan Khoronzhuk]

While compile natively, the hosts cflags and ldflags are equal to ones
used from HOSTCFLAGS and HOSTLDFLAGS. When cross compiling it should
have own, used for target arch. While verification, for arm, arm64 and
x86_64 the following flags were used alsways:

-Wall
-O2
-fomit-frame-pointer
-Wmissing-prototypes
-Wstrict-prototypes

So, add them as they were verified and used before adding
Makefile.target, but anyway limit it only for cross compile options as
for host can be some configurations when another options can be used,
So, for host arch samples left all as is, it allows to avoid potential
option mistmatches for existent environments.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>
---
 samples/bpf/Makefile | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 1579cc16a1c2..b5c87a8b8b51 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -178,8 +178,17 @@ CLANG_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
 TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR)
 endif
 
+ifdef CROSS_COMPILE
+TPROGS_CFLAGS += -Wall
+TPROGS_CFLAGS += -O2
+TPROGS_CFLAGS += -fomit-frame-pointer
+TPROGS_CFLAGS += -Wmissing-prototypes
+TPROGS_CFLAGS += -Wstrict-prototypes
+else
 TPROGS_LDLIBS := $(KBUILD_HOSTLDLIBS)
 TPROGS_CFLAGS += $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS)
+endif
+
 TPROGS_CFLAGS += -I$(objtree)/usr/include
 TPROGS_CFLAGS += -I$(srctree)/tools/lib/bpf/
 TPROGS_CFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
-- 
2.17.1