Stephen Hemminger wrote:

On Tue, 27 Feb 2018 14:06:50 +0200
Serhey Popovych [off-list ref] wrote:

quoted

Since commit 596b1c94aa38 ("iproute: build more easily on Android"),
iproute2 uses types __kernel_long_t and __kernel_ulong_t but does not
provide internal definitions for it.

This means that compilation using kernel headers that are older than 3.4
(where these types were added) will fail. This situation may be uncommon
for native compilation, but not uncommon for cross compilation where the
toolchains may be a bit older.

Provide the necessary types internally if not provided by the kernel
headers to fix compilation in such cases.

Co-Developed-by: Serhii Popovych <redacted>
Signed-off-by: Thomas De Schampheleire <redacted>
Signed-off-by: Serhey Popovych <redacted>
---
 Makefile                              |    5 ++++-
 include/compat/kernel/linux/sysinfo.h |   14 ++++++++++++++

Why not just start a single file include/compat.h which is what
other software does.

Yes it is good, but not for our case. We use include_next to define
__kernel_long_t and __kernel_ulong_t types if they not defined. If doing
single <compat.h> we need to include it in nearly all .c files as first
include file.

I also start thinking on single <compat.h> and found it bit complicated
than just adding header, (re)defining functionality and then include_next.

Doing fine grained kernel and libc per file makes it more painful.

Agree, and we already have <netinet/tcp.h> done using similar schema
that is reverted with this series.