after two days having problems installing ipsec tools on a brand new slack (13.37) i finally made it. After all i still don't know wtf gone wrong and having this message
In file included from ../../src/include-glibc/linux/pfkeyv2.h:9:0,
../../src/include-glibc/linux/types.h:13:2: warning: #warning "Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders"
By the way the solution worked for me was to edit the
and remove the -Werror option from CFLAGS.
Still got the message but installation finished.....