diff --git a/config.mk b/config.mk
index af6a1b4..47df220 100644
--- a/config.mk
+++ b/config.mk
@@ -103,7 +103,7 @@ INCS = ${GIRARA_INC} ${GTK_INC} ${GTHREAD_INC} ${GMODULE_INC} ${GLIB_INC}
 LIBS = ${GIRARA_LIB} ${GTK_LIB} ${GTHREAD_LIB} ${GMODULE_LIB} ${GLIB_LIB} -lpthread -lm
 
 # flags
-CFLAGS += -std=c99 -pedantic -Wall -Wno-format-zero-length -Wextra $(INCS)
+CFLAGS += -std=c11 -pedantic -Wall -Wno-format-zero-length -Wextra $(INCS)
 
 # debug
 DFLAGS ?= -g