diff --git a/src/location.h b/src/location.h
index 4c2b410d..5ebb92e3 100644
--- a/src/location.h
+++ b/src/location.h
@@ -88,7 +88,7 @@ typedef struct
 
 } location;
 
-#define YYLTYPE location
+#define GRAM_LTYPE location
 
 #define EMPTY_LOCATION_INIT {{NULL, 0, 0}, {NULL, 0, 0}}
 extern location const empty_location;
diff --git a/src/parse-gram.y b/src/parse-gram.y
index 3120bfc2..6a49923c 100644
--- a/src/parse-gram.y
+++ b/src/parse-gram.y
@@ -94,14 +94,14 @@ current_lhs(symbol *sym, location loc, named_ref *ref)
 %}
 
 %debug
-%verbose
-%defines
-%locations
-%pure-parser
-%error-verbose
+%define api.prefix "gram_"
+%define api.pure
 %define parse.lac full
-%name-prefix="gram_"
+%defines
+%error-verbose
 %expect 0
+%locations
+%verbose
 
 %initial-action
 {
diff --git a/src/scan-gram.h b/src/scan-gram.h
index ed973c78..72138a27 100644
--- a/src/scan-gram.h
+++ b/src/scan-gram.h
@@ -32,7 +32,7 @@ void gram_scanner_last_string_free (void);
 extern FILE *gram_out;
 extern int gram_lineno;
 
-# define GRAM_LEX_DECL int gram_lex (YYSTYPE *val, location *loc)
+# define GRAM_LEX_DECL int gram_lex (GRAM_STYPE *val, location *loc)
 GRAM_LEX_DECL;
 
 #endif /* !SCAN_GRAM_H_ */