alfred uses any netlink library which is (more or less) compatible with libnl-3. This is for example libnl-tiny on OpenWrt.

Programs and libraries which are build against libnl-tiny must be build with _GNU_SOURCE enabled to have some types in its headers defined. Thus _GNU_SOURCE is enabled in the OpenWrt alfred package since 2016.3. But sometimes using _GNU_SOURCE and sometimes not using it can have severe side effects which are non-trivial to debug when the developer is not also using the same _GNU_SOURCE preprocessor define. Thus enable _GNU_SOURCE by default to have similar behavior (defines, type definitions, structure members, ...) from headers like on OpenWrt.

Signed-off-by: Sven Eckelmann sven@narfation.org --- Makefile | 1 + gpsd/Makefile | 1 + vis/Makefile | 1 + 3 files changed, 3 insertions(+)

diff --git a/Makefile b/Makefile index 6daa904..552e690 100755 --- a/Makefile +++ b/Makefile @@ -36,6 +36,7 @@ MANPAGE = man/alfred.8

# alfred flags and options CFLAGS += -pedantic -Wall -W -std=gnu99 -fno-strict-aliasing -MD -MP +CPPFLAGS += -D_GNU_SOURCE LDLIBS += -lrt

# Turn on alfred capability dropping by default - set this to n if you don't want/need it diff --git a/gpsd/Makefile b/gpsd/Makefile index bae5660..b6172d9 100755 --- a/gpsd/Makefile +++ b/gpsd/Makefile @@ -25,6 +25,7 @@ MANPAGE = man/alfred-gpsd.8

# alfred flags and options CFLAGS += -pedantic -Wall -W -std=gnu99 -fno-strict-aliasing -MD -MP +CPPFLAGS += -D_GNU_SOURCE

# disable verbose output ifneq ($(findstring $(MAKEFLAGS),s),s) diff --git a/vis/Makefile b/vis/Makefile index fd99f49..22483a5 100755 --- a/vis/Makefile +++ b/vis/Makefile @@ -27,6 +27,7 @@ MANPAGE = man/batadv-vis.8

# batadv-vis flags and options CFLAGS += -pedantic -Wall -W -std=gnu99 -fno-strict-aliasing -MD -MP +CPPFLAGS += -D_GNU_SOURCE LDLIBS += -lrt

# disable verbose output