Merge branch 'topic/kliemann/certified-rts_64_shared_build' into '384…

…1-W518-004'

Allow overriding library version

See merge request eng/toolchain/bb-runtimes!70

support/data/target_options.gpr.in

@@ -11,7 +11,7 @@ abstract project Target_Options is
   Lib : Lib_Type := external ("LIBRARY_TYPE", "static");
 
   --  GNAT version string
-  Version := "{gnat_version}";
+  Version := external ("GNAT_VERSION", "{gnat_version}");
 
   --  COMFLAGS here is common flags (used for C and Ada).
   COMFLAGS := ("{common_flags}");