diff --git a/src/backend/tsearch/wparser_def.c b/src/backend/tsearch/wparser_def.c
index a3e5baf9782..98029e78fb4 100644
--- a/src/backend/tsearch/wparser_def.c
+++ b/src/backend/tsearch/wparser_def.c
@@ -2039,6 +2039,9 @@ hlCover(HeadlineParsedText *prs, TSQuery query, int max_cover,
 				nextpmax;
 	hlCheck		ch;
 
+	if (query->size <= 0)
+		return false;			/* empty query matches nothing */
+
 	/*
 	 * We look for the earliest, shortest substring of prs->words that
 	 * satisfies the query.  Both the pmin and pmax indices must be words
@@ -2343,7 +2346,8 @@ mark_hl_fragments(HeadlineParsedText *prs, TSQuery query, bool highlightall,
 	/* show the first min_words words if we have not marked anything */
 	if (num_f <= 0)
 	{
-		startpos = endpos = curlen = 0;
+		startpos = curlen = 0;
+		endpos = -1;
 		for (i = 0; i < prs->curwords && curlen < min_words; i++)
 		{
 			if (!NONWORDTOKEN(prs->words[i].type))
@@ -2498,7 +2502,7 @@ mark_hl_words(HeadlineParsedText *prs, TSQuery query, bool highlightall,
 		if (bestlen < 0)
 		{
 			curlen = 0;
-			pose = 0;
+			pose = -1;
 			for (i = 0; i < prs->curwords && curlen < min_words; i++)
 			{
 				if (!NONWORDTOKEN(prs->words[i].type))
diff --git a/src/test/regress/expected/tsearch.out b/src/test/regress/expected/tsearch.out
index 45b92a63388..4e52edf610f 100644
--- a/src/test/regress/expected/tsearch.out
+++ b/src/test/regress/expected/tsearch.out
@@ -1990,6 +1990,27 @@ to_tsquery('english','Lorem') && phraseto_tsquery('english','ullamcorper urna'),
  <b>Lorem</b> ipsum <b>urna</b>.  Nullam nullam <b>ullamcorper</b> <b>urna</b>
 (1 row)
 
+-- Edge cases with empty query
+SELECT ts_headline('english',
+'', ''::tsquery);
+NOTICE:  text-search query doesn't contain lexemes: ""
+LINE 2: '', ''::tsquery);
+            ^
+ ts_headline 
+-------------
+ 
+(1 row)
+
+SELECT ts_headline('english',
+'foo bar', ''::tsquery);
+NOTICE:  text-search query doesn't contain lexemes: ""
+LINE 2: 'foo bar', ''::tsquery);
+                   ^
+ ts_headline 
+-------------
+ foo bar
+(1 row)
+
 --Rewrite sub system
 CREATE TABLE test_tsquery (txtkeyword TEXT, txtsample TEXT);
 \set ECHO none
diff --git a/src/test/regress/sql/tsearch.sql b/src/test/regress/sql/tsearch.sql
index d929210998a..168eb0b9713 100644
--- a/src/test/regress/sql/tsearch.sql
+++ b/src/test/regress/sql/tsearch.sql
@@ -549,6 +549,12 @@ SELECT ts_headline('english',
 to_tsquery('english','Lorem') && phraseto_tsquery('english','ullamcorper urna'),
 'MaxFragments=100, MaxWords=100, MinWords=1');
 
+-- Edge cases with empty query
+SELECT ts_headline('english',
+'', ''::tsquery);
+SELECT ts_headline('english',
+'foo bar', ''::tsquery);
+
 --Rewrite sub system
 
 CREATE TABLE test_tsquery (txtkeyword TEXT, txtsample TEXT);