Fix possible use of uninitialised value in ts_headline()

Found during investigation of failure of skink buildfarm member and its
valgrind report.

Backpatch to all supported branches

diff --git a/src/backend/tsearch/wparser_def.c b/src/backend/tsearch/wparser_def.c
index 2faa15ebd4cb6fbd7f5bf7f402abdbcf9a2b68ae..ca352af331588ea1cbfe18fe3dcf9a3e5fdd104b 100644 (file)
--- a/src/backend/tsearch/wparser_def.c
+++ b/src/backend/tsearch/wparser_def.c
@@ -2465,6 +2465,8 @@ mark_hl_words(HeadlineParsedText *prs, TSQuery query, int highlight,
            }
            else
            {                   /* shorter cover :((( */
+               if (i > q)
+                   i = q;
                for (; curlen > min_words; i--)
                {
                    if (!NONWORDTOKEN(prs->words[i].type))