[PATCH RFC v2 2/5] samples/bpf: Enable cross compiler support

From: Joel Fernandes
Date: Mon Aug 07 2017 - 09:06:29 EST


When cross compiling, bpf samples use HOSTCC, however what we really want is to
use the cross compiler to build for the cross target since that is what will
help run the BPF target code. Detect this and also set -static as LDFLAGS
since often times we don't have control over what C library the cross target is
running and its not smart to rely on it.

Signed-off-by: Joel Fernandes <joelaf@xxxxxxxxxx>
---
samples/bpf/Makefile | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 6c7468eb3684..e5642c8c144d 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -152,6 +152,12 @@ HOSTLOADLIBES_test_map_in_map += -lelf
LLC ?= llc
CLANG ?= clang

+# Detect that we're cross compiling and use the right compilers and flags
+ifdef CROSS_COMPILE
+HOSTCC = $(CROSS_COMPILE)gcc
+HOSTLDFLAGS += -static
+endif
+
# Trick to allow make to be run from this directory
all:
$(MAKE) -C ../../ $(CURDIR)/
--
2.14.0.rc1.383.gd1ce394fe2-goog