diff --git a/src/espeak-ng.c b/src/espeak-ng.c
index 48fd03fc..a894d5d3 100644
--- a/src/espeak-ng.c
+++ b/src/espeak-ng.c
@@ -71,6 +71,10 @@ static const char *help_text =
     "--compile=<voice name>\n"
     "\t   Compile pronunciation rules and dictionary from the current\n"
     "\t   directory. <voice name> specifies the language\n"
+    "--compile-debug=<voice name>\n"
+    "\t   Compile pronunciation rules and dictionary from the current\n"
+    "\t   directory, including line numbers for use with -X.\n"
+    "\t   <voice name> specifies the language\n"
     "--compile-mbrola=<voice name>\n"
     "\t   Compile an MBROLA voice\n"
     "--compile-intonations\n"
diff --git a/src/speak-ng.c b/src/speak-ng.c
index c5d7cda1..d735fda4 100644
--- a/src/speak-ng.c
+++ b/src/speak-ng.c
@@ -98,6 +98,10 @@ static const char *help_text =
     "--compile=<voice name>\n"
     "\t   Compile pronunciation rules and dictionary from the current\n"
     "\t   directory. <voice name> specifies the language\n"
+    "--compile-debug=<voice name>\n"
+    "\t   Compile pronunciation rules and dictionary from the current\n"
+    "\t   directory, including line numbers for use with -X.\n"
+    "\t   <voice name> specifies the language\n"
     "--ipa      Write phonemes to stdout using International Phonetic Alphabet\n"
     "--path=\"<path>\"\n"
     "\t   Specifies the directory containing the espeak-data directory\n"