diff --git a/src/missed_spans.rs b/src/missed_spans.rs
index d6157cd6a29..537e9eb7efe 100644
--- a/src/missed_spans.rs
+++ b/src/missed_spans.rs
@@ -173,7 +173,7 @@ impl<'a> FmtVisitor<'a> {
                         if !subslice
                                .split('\n')
                                .map(|s| s.trim_left())
-                               .any(|s| s.len() > 2 && &s[0..2] == "/*") {
+                               .any(|s| s.len() >= 2 && &s[0..2] == "/*") {
                             // Add a newline after line comments
                             self.buffer.push_str("\n");
                         }
diff --git a/tests/target/issue-1598.rs b/tests/target/issue-1598.rs
new file mode 100644
index 00000000000..c7e02c961a6
--- /dev/null
+++ b/tests/target/issue-1598.rs
@@ -0,0 +1,6 @@
+fn main() {
+    //foo
+    /*
+     */
+    format!("hello");
+}