On Thu, Dec 26, 2019, at 04:49, David Miller wrote:

From: Rich Felker <dalias@libc.org>
Date: Wed, 25 Dec 2019 20:05:15 -0500

quoted

On Wed, Dec 25, 2019 at 04:34:11PM -0800, David Miller wrote:

quoted

I find it really strange that this, therefore, only happens for musl
and we haven't had thousands of reports of this conflict with glibc
over the years.

It's possible that there's software that's including just one of the
headers conditional on __GLIBC__, and including both otherwise, or
something like that. Arguably this should be considered unsupported
usage; there are plenty of headers where that doesn't work and
shouldn't be expected to.

I don't buy that, this is waaaaaay too common a header to use.

In case of net-tools, only <linux/ip.h> is included, and never <netinet/ip.h> directly. Chances are in musl the indirect include tree happens to be different and conflicting, while in glibc it is not.

Please investigate.

Daniel