When we build n-dhcp4 for NetworkManager we get a compiler warning.
This can also be reproduced by building n-dhcp4 alone:
$ CFLAGS='-Werror=declaration-after-statement' meson build && ninja -C build
...
[36/47] Compiling C object 'src/25a6634@@ndhcp4-private@sta/n-dhcp4-outgoing.c.o'.
FAILED: src/25a6634@@ndhcp4-private@sta/n-dhcp4-outgoing.c.o
ccache cc -Isrc/25a6634@@ndhcp4-private@sta -Isrc -I../src -Isubprojects/c-list/src -I../subprojects/c-list/src -Isubprojects/c-siphash/src -I../subprojects/c-siphash/src -Isubprojects/c-stdaux/src -I../subprojects/c-stdaux/src -fdiagnostics-color=always -pipe -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -std=c11 -g -D_GNU_SOURCE -Werror=declaration-after-statement -fPIC -fvisibility=hidden -fno-common -MD -MQ 'src/25a6634@@ndhcp4-private@sta/n-dhcp4-outgoing.c.o' -MF 'src/25a6634@@ndhcp4-private@sta/n-dhcp4-outgoing.c.o.d' -o 'src/25a6634@@ndhcp4-private@sta/n-dhcp4-outgoing.c.o' -c ../src/n-dhcp4-outgoing.c
../src/n-dhcp4-outgoing.c: In function ‘n_dhcp4_outgoing_new’:
../src/n-dhcp4-outgoing.c:63:9: error: ISO C90 forbids mixed declarations and code [-Werror=declaration-after-statement]
63 | static_assert(N_DHCP4_NETWORK_IP_MINIMUM_MAX_SIZE >= N_DHCP4_OUTGOING_MAX_PHDR +
| ^~~~~~~~~~~~~
(cherry picked from commit 9e7ca3e091)
In particular, avoid including linux/netdevice.h from headers. This is
not a problem on newer distros, but required for CentOS 7.6.
Signed-off-by: Tom Gundersen <teg@jklm.no>
