| Message ID | 20190605234722.2291-1-jakub.kicinski@netronome.com |
|---|---|
| State | Accepted |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [bpf-next,v2] samples: bpf: print a warning about headers_install | expand |
On Wed, Jun 05, 2019 at 04:47:22PM -0700, Jakub Kicinski wrote: > It seems like periodically someone posts patches to "fix" > header includes. The issue is that samples expect the > include path to have the uAPI headers (from usr/) first, > and then tools/ headers, so that locally installed uAPI > headers take precedence. This means that if users didn't > run headers_install they will see all sort of strange > compilation errors, e.g.: > > HOSTCC samples/bpf/test_lru_dist > samples/bpf/test_lru_dist.c:39:8: error: redefinition of ‘struct list_head’ > struct list_head { > ^~~~~~~~~ > In file included from samples/bpf/test_lru_dist.c:9:0: > ../tools/include/linux/types.h:69:8: note: originally defined here > struct list_head { > ^~~~~~~~~ > > Try to detect this situation, and print a helpful warning. Acked-by: Martin KaFai Lau <kafai@fb.com>
On 06/06/2019 01:47 AM, Jakub Kicinski wrote: > It seems like periodically someone posts patches to "fix" > header includes. The issue is that samples expect the > include path to have the uAPI headers (from usr/) first, > and then tools/ headers, so that locally installed uAPI > headers take precedence. This means that if users didn't > run headers_install they will see all sort of strange > compilation errors, e.g.: > > HOSTCC samples/bpf/test_lru_dist > samples/bpf/test_lru_dist.c:39:8: error: redefinition of ‘struct list_head’ > struct list_head { > ^~~~~~~~~ > In file included from samples/bpf/test_lru_dist.c:9:0: > ../tools/include/linux/types.h:69:8: note: originally defined here > struct list_head { > ^~~~~~~~~ > > Try to detect this situation, and print a helpful warning. > > v2: just use HOSTCC (Jiong). > > Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> > Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Applied, thanks!
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 253e5a2856be..4074a66a70ca 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -206,6 +206,15 @@ HOSTCC = $(CROSS_COMPILE)gcc CLANG_ARCH_ARGS = -target $(ARCH) endif +HDR_PROBE := $(shell echo "\#include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \ + $(HOSTCC) $(KBUILD_HOSTCFLAGS) -x c - -o /dev/null 2>/dev/null && \ + echo okay) + +ifeq ($(HDR_PROBE),) +$(warning WARNING: Detected possible issues with include path.) +$(warning WARNING: Please install kernel headers locally (make headers_install).) +endif + BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris) BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF) BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm')
It seems like periodically someone posts patches to "fix" header includes. The issue is that samples expect the include path to have the uAPI headers (from usr/) first, and then tools/ headers, so that locally installed uAPI headers take precedence. This means that if users didn't run headers_install they will see all sort of strange compilation errors, e.g.: HOSTCC samples/bpf/test_lru_dist samples/bpf/test_lru_dist.c:39:8: error: redefinition of ‘struct list_head’ struct list_head { ^~~~~~~~~ In file included from samples/bpf/test_lru_dist.c:9:0: ../tools/include/linux/types.h:69:8: note: originally defined here struct list_head { ^~~~~~~~~ Try to detect this situation, and print a helpful warning. v2: just use HOSTCC (Jiong). Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> --- samples/bpf/Makefile | 9 +++++++++ 1 file changed, 9 insertions(+)