diff --git a/src/gprlib.adb b/src/gprlib.adb
index 728f767..e47b79b 100644
--- a/src/gprlib.adb
+++ b/src/gprlib.adb
@@ -22,6 +22,7 @@
 
 with Ada.Command_Line;  use Ada.Command_Line;
 with Ada.Text_IO;       use Ada.Text_IO;
+with Ada.Strings.Fixed;
 
 with GNAT.Case_Util;            use GNAT.Case_Util;
 with GNAT.Directory_Operations; use GNAT.Directory_Operations;
@@ -1154,6 +1155,25 @@ begin
                      GNAT_Version := new String'(Line (6 .. Last));
                      GNAT_Version_Set := True;
 
+                     -- The version numbering scheme changed in GCC 5.
+                     -- If there is a dot in the version, and the part before
+                     -- the dot is 5 or greater, then use only that part in the
+                     -- library names.
+
+                     declare
+                        Pos : Natural := Ada.Strings.Fixed.Index (Line, ".", 6);
+                     begin
+                        if Pos > 0 then
+                           Pos := Pos - 1;  -- the last digit in the first part
+                           if Natural'Value (Line(6 .. Pos)) >= 5 then
+                              Last := Pos;
+                           end if;
+                        end if;
+                     exception
+                        when Constraint_Error =>
+                           null;  -- Not a number? Then let it be.
+                     end;
+
                      Libgnat :=
                        new String'
                          ("-lgnat-" & Line (6 .. Last));