[openwrt/openwrt] xdp-tools: don't rely on host bpf headers

[LEDE Commits]

dangole pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/f5d6ed3007cb04bfef388e986d3b148b609cb959

commit f5d6ed3007cb04bfef388e986d3b148b609cb959
Author: Daniel Golle <daniel at makrotopia.org>
AuthorDate: Mon Sep 12 01:13:59 2022 +0100

    xdp-tools: don't rely on host bpf headers
    
    xdp-tools build currently breaks on build hosts which do not have
    libbpf headers installed because the build system wrongly tries to
    use the host's include path.
    Properly pass path to libbpf headers to xdp-tools build system to
    fix build e.g. on the buildbots.
    
    Signed-off-by: Daniel Golle <daniel at makrotopia.org>
---
 package/network/utils/xdp-tools/Makefile | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/package/network/utils/xdp-tools/Makefile b/package/network/utils/xdp-tools/Makefile
index 32f302543a..42a8a0695b 100644
--- a/package/network/utils/xdp-tools/Makefile
+++ b/package/network/utils/xdp-tools/Makefile
@@ -85,7 +85,6 @@ CONFIGURE_VARS += \
 	CFLAGS="$(TARGET_CFLAGS)" \
 	LDFLAGS="$(TARGET_LDFLAGS)" \
 	CLANG="$(CLANG)" \
-	BPF_CFLAGS="$(BPF_CFLAGS)" \
 	BPF_TARGET="$(BPF_TARGET)" \
 	LLC="$(LLVM_LLC)"
 
@@ -93,6 +92,11 @@ MAKE_VARS += \
 	PREFIX=/usr \
 	RUNDIR=/tmp/run
 
+define Build/Configure
+	$(call Build/Configure/Default)
+	echo "BPF_CFLAGS += -I$(BPF_HEADERS_DIR)/tools/lib" >> $(PKG_BUILD_DIR)/config.mk
+endef
+
 define Build/InstallDev
 	$(INSTALL_DIR) $(1)/usr/include/xdp
 	$(CP) $(PKG_INSTALL_DIR)/usr/include/xdp/*.h $(1)/usr/include/xdp/