diff --git a/2020/burton/Makefile b/2020/burton/Makefile
index eea2eacba..7a2940505 100644
--- a/2020/burton/Makefile
+++ b/2020/burton/Makefile
@@ -76,7 +76,7 @@ CWARN= -Wall -Wextra -pedantic ${CSILENCE}
 #
 #CSTD=
 #CSTD= -ansi
-CSTD= -std=gnu99
+CSTD= -std=gnu17
 
 # Compiler bit architecture
 #