diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 55b957d251..e181a535eb 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -873,7 +873,7 @@ pgss_planner(Query *parse,
 			 int cursorOptions,
 			 ParamListInfo boundParams)
 {
-	PlannedStmt *result;
+	PlannedStmt *result = NULL;
 
 	/*
 	 * We can't process the query if no query_string is provided, as
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index c5cada55fb..660362dcc7 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -5064,7 +5064,7 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel,
 	int			server_version_num;
 	PgFdwSamplingMethod method = ANALYZE_SAMPLE_AUTO;	/* auto is default */
 	double		sample_frac = -1.0;
-	double		reltuples;
+	double		reltuples = 0.0;
 	unsigned int cursor_number;
 	StringInfoData sql;
 	PGresult   *volatile res = NULL;
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
index 52177759ab..be66b82d43 100644
--- a/src/backend/commands/trigger.c
+++ b/src/backend/commands/trigger.c
@@ -2313,7 +2313,7 @@ ExecCallTriggerFunc(TriggerData *trigdata,
 {
 	LOCAL_FCINFO(fcinfo, 0);
 	PgStat_FunctionCallUsage fcusage;
-	Datum		result;
+	Datum		result = PointerGetDatum(0);	/* keep compiler quiet */
 	MemoryContext oldContext;
 
 	/*
diff --git a/src/backend/libpq/be-fsstubs.c b/src/backend/libpq/be-fsstubs.c
index d189044a4f..6090197c84 100644
--- a/src/backend/libpq/be-fsstubs.c
+++ b/src/backend/libpq/be-fsstubs.c
@@ -482,7 +482,7 @@ be_lo_export(PG_FUNCTION_ARGS)
 {
 	Oid			lobjId = PG_GETARG_OID(0);
 	text	   *filename = PG_GETARG_TEXT_PP(1);
-	int			fd;
+	int			fd = -1;
 	int			nbytes,
 				tmp;
 	char		buf[BUFSIZE];
diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index 866d0d649a..4ae78d3a88 100644
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -1339,7 +1339,7 @@ pg_xmlCharStrndup(const char *str, size_t len)
 static char *
 xml_pstrdup_and_free(xmlChar *str)
 {
-	char	   *result;
+	char	   *result = NULL;
 
 	if (str)
 	{
@@ -1353,8 +1353,6 @@ xml_pstrdup_and_free(xmlChar *str)
 		}
 		PG_END_TRY();
 	}
-	else
-		result = NULL;
 
 	return result;
 }