diff --git a/src/backend/main/main.c b/src/backend/main/main.c
index 8d4218e00bf..a77e05da90f 100644
--- a/src/backend/main/main.c
+++ b/src/backend/main/main.c
@@ -189,7 +189,9 @@ main(int argc, char *argv[])
 	else if (argc > 1 && strcmp(argv[1], "--describe-config") == 0)
 		GucInfoMain();			/* does not return */
 	else if (argc > 1 && strcmp(argv[1], "--single") == 0)
-		PostgresMain(argc, argv, get_current_username(progname)); /* does not return */
+		PostgresMain(argc, argv,
+					 NULL,		/* no dbname */
+					 get_current_username(progname)); /* does not return */
 	else
 		PostmasterMain(argc, argv); /* does not return */
 	abort();						/* should not get here */
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 15c23204611..298ad5e1ec4 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -3943,7 +3943,7 @@ BackendRun(Port *port)
 	 * from ExtraOptions is (strlen(ExtraOptions) + 1) / 2; see
 	 * pg_split_opts().
 	 */
-	maxac = 5;					/* for fixed args supplied below */
+	maxac = 2;					/* for fixed args supplied below */
 	maxac += (strlen(ExtraOptions) + 1) / 2;
 
 	av = (char **) MemoryContextAlloc(TopMemoryContext,
@@ -3959,11 +3959,6 @@ BackendRun(Port *port)
 	 */
 	pg_split_opts(av, &ac, ExtraOptions);
 
-	/*
-	 * Tell the backend which database to use.
-	 */
-	av[ac++] = port->database_name;
-
 	av[ac] = NULL;
 
 	Assert(ac < maxac);
@@ -3986,7 +3981,7 @@ BackendRun(Port *port)
 	 */
 	MemoryContextSwitchTo(TopMemoryContext);
 
-	PostgresMain(ac, av, port->user_name);
+	PostgresMain(ac, av, port->database_name, port->user_name);
 }
 
 
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 587d065f1cc..f0783031808 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -3247,13 +3247,14 @@ get_stats_option_name(const char *arg)
  * coming from the client, or PGC_SUSET for insecure options coming from
  * a superuser client.
  *
- * Returns the database name extracted from the command line, if any.
+ * If a database name is present in the command line arguments, it's
+ * returned into *dbname (this is allowed only if *dbname is initially NULL).
  * ----------------------------------------------------------------
  */
-const char *
-process_postgres_switches(int argc, char *argv[], GucContext ctx)
+void
+process_postgres_switches(int argc, char *argv[], GucContext ctx,
+						  const char **dbname)
 {
-	const char *dbname;
 	bool		secure = (ctx == PGC_POSTMASTER);
 	int			errs = 0;
 	GucSource	gucsource;
@@ -3304,7 +3305,8 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx)
 
 			case 'b':
 				/* Undocumented flag used for binary upgrades */
-				IsBinaryUpgrade = true;
+				if (secure)
+					IsBinaryUpgrade = true;
 				break;
 
 			case 'C':
@@ -3321,7 +3323,8 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx)
 				break;
 
 			case 'E':
-				EchoQuery = true;
+				if (secure)
+					EchoQuery = true;
 				break;
 
 			case 'e':
@@ -3346,7 +3349,8 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx)
 				break;
 
 			case 'j':
-				UseNewLine = 0;
+				if (secure)
+					UseNewLine = 0;
 				break;
 
 			case 'k':
@@ -3464,13 +3468,10 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx)
 	}
 
 	/*
-	 * Should be no more arguments except an optional database name, and
-	 * that's only in the secure case.
+	 * Optional database name should be there only if *dbname is NULL.
 	 */
-	if (!errs && secure && argc - optind >= 1)
-		dbname = strdup(argv[optind++]);
-	else
-		dbname = NULL;
+	if (!errs && dbname && *dbname == NULL && argc - optind >= 1)
+		*dbname = strdup(argv[optind++]);
 
 	if (errs || argc != optind)
 	{
@@ -3499,8 +3500,6 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx)
 #ifdef HAVE_INT_OPTRESET
 	optreset = 1;				/* some systems need this too */
 #endif
-
-	return dbname;
 }
 
 
@@ -3510,14 +3509,16 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx)
  *
  * argc/argv are the command line arguments to be used.  (When being forked
  * by the postmaster, these are not the original argv array of the process.)
- * username is the (possibly authenticated) PostgreSQL user name to be used
- * for the session.
+ * dbname is the name of the database to connect to, or NULL if the database
+ * name should be extracted from the command line arguments or defaulted.
+ * username is the PostgreSQL user name to be used for the session.
  * ----------------------------------------------------------------
  */
 void
-PostgresMain(int argc, char *argv[], const char *username)
+PostgresMain(int argc, char *argv[],
+			 const char *dbname,
+			 const char *username)
 {
-	const char *dbname;
 	int			firstchar;
 	StringInfoData input_message;
 	sigjmp_buf	local_sigjmp_buf;
@@ -3564,7 +3565,7 @@ PostgresMain(int argc, char *argv[], const char *username)
 	/*
 	 * Parse command-line options.
 	 */
-	dbname = process_postgres_switches(argc, argv, PGC_POSTMASTER);
+	process_postgres_switches(argc, argv, PGC_POSTMASTER, &dbname);
 
 	/* Must have gotten a database name, or have a default (the username) */
 	if (dbname == NULL)
diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c
index da3127ea9c9..5b52bd27973 100644
--- a/src/backend/utils/init/postinit.c
+++ b/src/backend/utils/init/postinit.c
@@ -969,7 +969,7 @@ process_startup_options(Port *port, bool am_superuser)
 
 		Assert(ac < maxac);
 
-		(void) process_postgres_switches(ac, av, gucctx);
+		(void) process_postgres_switches(ac, av, gucctx, NULL);
 	}
 
 	/*
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index e6f0afbedfe..035a442e35f 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -69,9 +69,11 @@ extern void RecoveryConflictInterrupt(ProcSignalReason reason); /* called from S
 																 * handler */
 extern void prepare_for_client_read(void);
 extern void client_read_ended(void);
-extern const char *process_postgres_switches(int argc, char *argv[],
-						  GucContext ctx);
-extern void PostgresMain(int argc, char *argv[], const char *username) __attribute__((noreturn));
+extern void process_postgres_switches(int argc, char *argv[],
+						  GucContext ctx, const char **dbname);
+extern void PostgresMain(int argc, char *argv[],
+			 const char *dbname,
+			 const char *username) __attribute__((noreturn));
 extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);