diff --git a/sys/contrib/dev/acpica/compiler/aslutils.c b/sys/contrib/dev/acpica/compiler/aslutils.c
index 2bbc2705817b..a33a904f6d6f 100644
--- a/sys/contrib/dev/acpica/compiler/aslutils.c
+++ b/sys/contrib/dev/acpica/compiler/aslutils.c
@@ -126,7 +126,7 @@
 
 #ifdef _USE_BERKELEY_YACC
 extern const char * const       AslCompilername[];
-static const char * const       *yytname = &AslCompilername[255];
+static const char * const       *yytname = &AslCompilername[254];
 #else
 extern const char * const       yytname[];
 #endif