check that CC can build executables and use that compiler instead of HOSTCC
Suggested-by: Arnd Bergmann <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
---
Makefile | 5 +++++
net/Makefile | 4 ++++
net/bpfilter/Makefile | 2 ++
scripts/cc-can-link.sh | 11 +++++++++++
4 files changed, 22 insertions(+)
create mode 100755 scripts/cc-can-link.sh
diff --git a/Makefile b/Makefile
index 56ba070dfa09..62c110084fae 100644
--- a/Makefile
+++ b/Makefile
@@ -510,6 +510,11 @@ ifeq ($(call shell-cached,$(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $
KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
endif
+ifeq ($(call shell-cached,$(CONFIG_SHELL) $(srctree)/scripts/cc-can-link.sh $(CC)), y)
+ CC_CAN_LINK := y
+ export CC_CAN_LINK
+endif
+
ifeq ($(config-targets),1)
# ===========================================================================
# *config targets only - make sure prerequisites are updated, and descend
diff --git a/net/Makefile b/net/Makefile
index bdaf53925acd..13ec0d5415c7 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -20,7 +20,11 @@ obj-$(CONFIG_TLS) += tls/
obj-$(CONFIG_XFRM) += xfrm/
obj-$(CONFIG_UNIX) += unix/
obj-$(CONFIG_NET) += ipv6/
+ifneq ($(CC_CAN_LINK),y)
+$(warning CC cannot link executables. Skipping bpfilter.)
+else
obj-$(CONFIG_BPFILTER) += bpfilter/
+endif
obj-$(CONFIG_PACKET) += packet/
obj-$(CONFIG_NET_KEY) += key/
obj-$(CONFIG_BRIDGE) += bridge/
diff --git a/net/bpfilter/Makefile b/net/bpfilter/Makefile
index 3f3cb87c668f..aafa72001fcd 100644
--- a/net/bpfilter/Makefile
+++ b/net/bpfilter/Makefile
@@ -6,6 +6,8 @@
hostprogs-y := bpfilter_umh
bpfilter_umh-objs := main.o
HOSTCFLAGS += -I. -Itools/include/ -Itools/include/uapi
+HOSTCC := $(CC)
+
ifeq ($(CONFIG_BPFILTER_UMH), y)
# builtin bpfilter_umh should be compiled with -static
# since rootfs isn't mounted at the time of __init
diff --git a/scripts/cc-can-link.sh b/scripts/cc-can-link.sh
new file mode 100755
index 000000000000..208eb2825dab
--- /dev/null
+++ b/scripts/cc-can-link.sh
@@ -0,0 +1,11 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+cat << "END" | $@ -x c - -o /dev/null >/dev/null 2>&1 && echo "y"
+#include <stdio.h>
+int main(void)
+{
+ printf("");
+ return 0;
+}
+END
--
2.9.5
From: Alexei Starovoitov <[email protected]>
Date: Mon, 4 Jun 2018 19:53:41 -0700
> check that CC can build executables and use that compiler instead of HOSTCC
>
> Suggested-by: Arnd Bergmann <[email protected]>
> Signed-off-by: Alexei Starovoitov <[email protected]>
Applied, thanks Alexei.