[Ada] Initialize gnat_argc/gnat_argv only the first time

2019-08-20  Philippe Gil  <gil@adacore.com>

gcc/ada/

	* bindgen.adb (Gen_Main): Set gnat_argc/gnat_argv to argc/argv
	only when still uninitialized.

From-SVN: r274716

gcc/ada/ChangeLog

+2019-08-20  Philippe Gil  <gil@adacore.com>
+
+	* bindgen.adb (Gen_Main): Set gnat_argc/gnat_argv to argc/argv
+	only when still uninitialized.
+
 2019-08-20  Bob Duff  <duff@adacore.com>
 
 	* libgnat/g-comlin.ads (Exit_From_Command_Line): Fix

gcc/ada/bindgen.adb

@@ -1826,18 +1826,25 @@ package body Bindgen is
 
       WBI ("   begin");
 
-      --  Acquire command line arguments if present on target
+      --  Acquire command-line arguments if present on target
 
       if CodePeer_Mode then
          null;
 
       elsif Command_Line_Args_On_Target then
-         WBI ("      gnat_argc := argc;");
-         WBI ("      gnat_argv := argv;");
+
+         --  Initialize gnat_argc/gnat_argv only if not already initialized,
+         --  to avoid losing the result of any command-line processing done by
+         --  earlier GNAT run-time initialization.
+
+         WBI ("      if gnat_argc = 0 then");
+         WBI ("         gnat_argc := argc;");
+         WBI ("         gnat_argv := argv;");
+         WBI ("      end if;");
          WBI ("      gnat_envp := envp;");
          WBI ("");
 
-      --  If configurable run time and no command line args, then nothing needs
+      --  If configurable run-time and no command-line args, then nothing needs
       --  to be done since the gnat_argc/argv/envp variables are suppressed in
       --  this case.