diff --git a/src/backend/commands/functioncmds.c b/src/backend/commands/functioncmds.c
index e7cb5c65e9..73f9fe1f70 100644
--- a/src/backend/commands/functioncmds.c
+++ b/src/backend/commands/functioncmds.c
@@ -964,13 +964,13 @@ interpret_AS_clause(Oid languageOid, const char *languageName,
 		}
 
 		/*
-		 * We must put something in prosrc.  For the moment, just record an
-		 * empty string.  It might be useful to store the original text of the
-		 * CREATE FUNCTION statement --- but to make actual use of that in
-		 * error reports, we'd also have to adjust readfuncs.c to not throw
-		 * away node location fields when reading prosqlbody.
+		 * Use the text of the CREATE FUNCTION statement as prosrc.  Note that
+		 * this might be more text than strictly necessary, if CREATE FUNCTION
+		 * is part of a multi-statement string; but trimming it would require
+		 * adjusting the location fields in prosqlbody, which seems like way
+		 * more trouble than the case is worth.
 		 */
-		*prosrc_str_p = pstrdup("");
+		*prosrc_str_p = pstrdup(queryString);
 
 		/* But we definitely don't need probin. */
 		*probin_str_p = NULL;