diff --git a/plugins/kapt3/kapt3-base/src/org/jetbrains/kotlin/kapt3/base/javac/KaptJavaLog.kt b/plugins/kapt3/kapt3-base/src/org/jetbrains/kotlin/kapt3/base/javac/KaptJavaLog.kt
index 546415fc22f..b43e68d34f1 100644
--- a/plugins/kapt3/kapt3-base/src/org/jetbrains/kotlin/kapt3/base/javac/KaptJavaLog.kt
+++ b/plugins/kapt3/kapt3-base/src/org/jetbrains/kotlin/kapt3/base/javac/KaptJavaLog.kt
@@ -152,7 +152,7 @@ class KaptJavaLog(
 
         val formattedMessage = diagnosticFormatter.format(diagnostic, javacMessages.currentLocale)
             .lines()
-            .joinToString(LINE_SEPARATOR) { original ->
+            .joinToString(LINE_SEPARATOR, postfix = LINE_SEPARATOR) { original ->
                 // Kotlin location is put as a sub-diagnostic, so the formatter indents it with four additional spaces (6 in total).
                 // It looks weird, especially in the build log inside IntelliJ, so let's make things a bit better.
                 val trimmed = original.trimStart()
@@ -263,4 +263,4 @@ private data class KotlinFileObject(val file: File) : SimpleJavaFileObject(file.
     override fun getLastModified() = file.lastModified()
     override fun openReader(ignoreEncodingErrors: Boolean) = file.reader()
     override fun delete() = file.delete()
-}
\ No newline at end of file
+}