diff --git a/security/snort2pfcd/Makefile b/security/snort2pfcd/Makefile
index 599201bd7bb1..71fa4cba08cd 100644
--- a/security/snort2pfcd/Makefile
+++ b/security/snort2pfcd/Makefile
@@ -14,6 +14,7 @@ LICENSE_FILE=	${WRKSRC}/COPYING
 LIB_DEPENDS=	libcidr.so:devel/libcidr
 RUN_DEPENDS=	snort:security/snort
 
+USES=		compiler:c11
 USE_RC_SUBR=	snort2pfcd
 PLIST_FILES=	man/man8/snort2pfcd.8.gz \
 		sbin/snort2pfcd
diff --git a/security/snort2pfcd/files/patch-Makefile b/security/snort2pfcd/files/patch-Makefile
new file mode 100644
index 000000000000..8799c7f6a2aa
--- /dev/null
+++ b/security/snort2pfcd/files/patch-Makefile
@@ -0,0 +1,11 @@
+--- Makefile.orig	2020-11-14 01:58:17 UTC
++++ Makefile
+@@ -2,7 +2,7 @@ PROG= snort2pfcd
+ SRCS= main.c parser.c kevent.c spfc.c tools.c
+ MAN= ${PROG}.8
+ CFLAGS+= -Wall -Wextra -pipe -fno-strict-aliasing -pedantic -pthread -Wno-unused-parameter \
+--Wno-long-long -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wstring-conversion \
++-Wno-long-long -Wimplicit-fallthrough -Wno-noexcept-type \
+ -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -D_REENTRANT -D_THREAD_SAFE -D_VERSION="${1}" -I${LOCALBASE}/include
+ 
+ LDFLAGS+=-lutil -L${LOCALBASE}/lib -lcidr