X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Flanguage%2Flexer%2Flexer.c;h=b6e5fc4e39683ef3296b7e21753af463d6aaec78;hb=2bad4e1d02bd2d33de548ec8cf145999700a1aa4;hp=39b674c554d6891e037e43a97cc6d41b61a25f39;hpb=5f7f751a47c68946a0fcbc9898f43f5499c5c6c5;p=pspp-builds.git

diff --git a/src/language/lexer/lexer.c b/src/language/lexer/lexer.c
index 39b674c5..b6e5fc4e 100644
--- a/src/language/lexer/lexer.c
+++ b/src/language/lexer/lexer.c
@@ -111,11 +111,14 @@ lex_create (bool (*read_line_func) (struct string *, bool *))
 void
 lex_destroy (struct lexer *lexer)
 {
-  ds_destroy (&lexer->put_tokstr);
-  ds_destroy (&lexer->tokstr);
-  ds_destroy (&lexer->line_buffer);
+  if ( NULL != lexer ) 
+    {
+      ds_destroy (&lexer->put_tokstr);
+      ds_destroy (&lexer->tokstr);
+      ds_destroy (&lexer->line_buffer);
 
-  free (lexer);
+      free (lexer);
+    }
 }