On Mon, Sep 16, 2019 at 01:44:23PM -0700, Andrii Nakryiko wrote:
On Mon, Sep 16, 2019 at 3:59 AM Ivan Khoronzhuk
<ivan.khoronzhuk@xxxxxxxxxx> wrote:
For arm, -D__LINUX_ARM_ARCH__=X is min version used as instruction
set selector and is absolutely required while parsing some parts of
headers. It's present in KBUILD_CFLAGS but not in autoconf.h, so let's
retrieve it from and add to programs cflags. In another case errors
like "SMP is not supported" for armv7 and bunch of other errors are
issued resulting to incorrect final object.
---
samples/bpf/Makefile | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 8ecc5d0c2d5b..d3c8db3df560 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -185,6 +185,16 @@ HOSTLDLIBS_map_perf_test += -lrt
HOSTLDLIBS_test_overhead += -lrt
HOSTLDLIBS_xdpsock += -pthread
+ifeq ($(ARCH), arm)
+# Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux
+# headers when arm instruction set identification is requested.
+ARM_ARCH_SELECTOR = $(shell echo "$(KBUILD_CFLAGS) " | \
+ sed 's/[[:blank:]]/\n/g' | sed '/^-D__LINUX_ARM_ARCH__/!d')
Does the following work exactly like that without shelling out (and
being arguably simpler)?
ARM_ARCH_SELECTOR = $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS))
+
+CLANG_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
+KBUILD_HOSTCFLAGS := $(ARM_ARCH_SELECTOR)
Isn't this clearing out previous value of KBUILD_HOSTCFLAGS? Is that
intentional, or it was supposed to be += here?
+endif
+
# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
# make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang
LLC ?= llc
--
2.17.1
Just left from previous version filtering all -D options.
Will update in next v., SELECTOR also.
--
Regards,
Ivan Khoronzhuk
