diff --git a/Objects/fileobject.c b/Objects/fileobject.c
index 16786f8..271f4cd 100644
--- a/Objects/fileobject.c
+++ b/Objects/fileobject.c
@@ -718,6 +718,7 @@
 		int c;
 		c = GETC(f->f_fp);
 		if (c == '\n') {
+			f->f_newlinetypes |= NEWLINE_CRLF;
 			pos++;
 			f->f_skipnextlf = 0;
 		} else if (c != EOF) ungetc(c, f->f_fp);