diff --git a/configure.ac b/configure.ac
index c2db1a3..fb8b7cd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -26,10 +26,10 @@ AC_ARG_ENABLE([debug],
[debug=no])
if test "x$debug" = "xyes"; then
- AS_COMPILER_FLAGS(AM_CFLAGS, "-g -ggdb -O0 -pipe -pedantic -Wall -Wextra -Waggregate-return -Wcast-align -Wdeclaration-after-statement -Wformat-nonliteral -Wformat-security -Winit-self -Winline -Winvalid-pch -Wmissing-declarations -Wmissing-include-dirs -Wmissing-noreturn -Wmissing-prototypes -Wnested-externs -Wno-missing-field-initializers -Wno-unused-parameter -Wold-style-definition -Wpointer-arith -Wredundant-decls -Wshadow -Wstrict-prototypes -Wswitch-enum -Wundef -Wunsafe-loop-optimizations -Wwrite-strings")
+ AS_COMPILER_FLAGS(AM_CFLAGS, "-std=c89 -g -ggdb -O0 -pipe -pedantic -Wall -Wextra -Waggregate-return -Wcast-align -Wdeclaration-after-statement -Wformat-nonliteral -Wformat-security -Winit-self -Winline -Winvalid-pch -Wmissing-declarations -Wmissing-include-dirs -Wmissing-noreturn -Wmissing-prototypes -Wnested-externs -Wno-missing-field-initializers -Wno-unused-parameter -Wold-style-definition -Wpointer-arith -Wredundant-decls -Wshadow -Wstrict-prototypes -Wswitch-enum -Wundef -Wunsafe-loop-optimizations -Wwrite-strings")
AC_DEFINE([DEBUG], [], [Turn on debug mode])
else
- AS_COMPILER_FLAGS(AM_CFLAGS, "-O2")
+ AS_COMPILER_FLAGS(AM_CFLAGS, "-O2 -pipe")
fi
diff --git a/src/config.c b/src/config.c
index cb786ce..195fa37 100644
--- a/src/config.c
+++ b/src/config.c
@@ -16,6 +16,8 @@
* along with this program. If not, see .
*/
+#define _POSIX_C_SOURCE 201112L
+
#include /* inet_pton */
#include /* struct ifaddrs, getifaddrs, freeifaddrs */
#include /* getnameinfo, NI_NUMERICHOST */
diff --git a/src/transmitter.c b/src/transmitter.c
index d97b5f5..3e9295a 100644
--- a/src/transmitter.c
+++ b/src/transmitter.c
@@ -16,6 +16,8 @@
* along with this program. If not, see .
*/
+#define _DEFAULT_SOURCE
+
#include /* struct ifreq */
#include /* {P,A}F_PACKET, ETH_P_*, socket, SOCK_RAW,
* setsockopt, SOL_SOCKET, SO_BINDTODEVICE,
diff --git a/src/wrapper.c b/src/wrapper.c
index 754db71..bc8bb32 100644
--- a/src/wrapper.c
+++ b/src/wrapper.c
@@ -16,6 +16,8 @@
* along with this program. If not, see .
*/
+#define _DEFAULT_SOURCE
+
#include /* inet_pton */
#include /* struct ethtool_value */
#include /* ETH_P_ALL */