diff --git a/crypto/x509/x509_meth.c b/crypto/x509/x509_meth.c
index 05ed4bf863..9dc587a092 100644
--- a/crypto/x509/x509_meth.c
+++ b/crypto/x509/x509_meth.c
@@ -58,9 +58,9 @@ int (*X509_LOOKUP_meth_get_new_item(const X509_LOOKUP_METHOD* method))
 
 int X509_LOOKUP_meth_set_free(
     X509_LOOKUP_METHOD *method,
-    void (*free) (X509_LOOKUP *ctx))
+    void (*free_fn) (X509_LOOKUP *ctx))
 {
-    method->free = free;
+    method->free = free_fn;
     return 1;
 }
 
diff --git a/include/openssl/x509_vfy.h b/include/openssl/x509_vfy.h
index a657ec216c..2adb155970 100644
--- a/include/openssl/x509_vfy.h
+++ b/include/openssl/x509_vfy.h
@@ -401,7 +401,7 @@ int (*X509_LOOKUP_meth_get_new_item(const X509_LOOKUP_METHOD* method))
     (X509_LOOKUP *ctx);
 
 int X509_LOOKUP_meth_set_free(X509_LOOKUP_METHOD *method,
-                              void (*free) (X509_LOOKUP *ctx));
+                              void (*free_fn) (X509_LOOKUP *ctx));
 void (*X509_LOOKUP_meth_get_free(const X509_LOOKUP_METHOD* method))
     (X509_LOOKUP *ctx);