[Ada] General purpose doubly linked list for compiler and tool use

This patch adds unit GNAT.Lists which currently contains the
implementation of a general purpose doubly linked list intended for use
by the compiler and the tools around it.

2018-08-21  Hristian Kirtchev  <kirtchev@adacore.com>

gcc/ada/

	* impunit.adb: Add g-lists to the set of non-implementation
	units.
	* libgnat/g-lists.adb, libgnat/g-lists.ads: New unit.
	* Makefile.rtl: Add g-lists to the set of non-tasking units.
	* gcc-interface/Make-lang.in: Add g-lists to the set of files
	used by gnat1.

gcc/testsuite/

	* gnat.dg/linkedlist.adb: New testcase.

From-SVN: r263714

gcc/ada/ChangeLog

+2018-08-21  Hristian Kirtchev  <kirtchev@adacore.com>
+
+	* impunit.adb: Add g-lists to the set of non-implementation
+	units.
+	* libgnat/g-lists.adb, libgnat/g-lists.ads: New unit.
+	* Makefile.rtl: Add g-lists to the set of non-tasking units.
+	* gcc-interface/Make-lang.in: Add g-lists to the set of files
+	used by gnat1.
+
 2018-08-21  Ed Schonberg  <schonberg@adacore.com>
 
 	* exp_ch9.adb (Reset_Scopes): Do not recurse into type

gcc/ada/Makefile.rtl

@@ -427,6 +427,7 @@ GNATRTL_NONTASKING_OBJS= \
   g-htable$(objext) \
   g-io$(objext) \
   g-io_aux$(objext) \
+  g-lists$(objext) \
   g-locfil$(objext) \
   g-mbdira$(objext) \
   g-mbflra$(objext) \

gcc/ada/gcc-interface/Make-lang.in

@@ -319,6 +319,7 @@ GNAT_ADA_OBJS =	\
  ada/libgnat/g-dynhta.o	\
  ada/libgnat/g-hesora.o	\
  ada/libgnat/g-htable.o	\
+ ada/libgnat/g-lists.o \
  ada/libgnat/g-spchge.o	\
  ada/libgnat/g-speche.o	\
  ada/libgnat/g-u3spch.o	\

gcc/ada/impunit.adb

@@ -281,6 +281,7 @@ package body Impunit is
     ("g-htable", F),  -- GNAT.Htable
     ("g-io    ", F),  -- GNAT.IO
     ("g-io_aux", F),  -- GNAT.IO_Aux
+    ("g-lists ", F),  -- GNAT.Lists
     ("g-locfil", F),  -- GNAT.Lock_Files
     ("g-mbdira", F),  -- GNAT.MBBS_Discrete_Random
     ("g-mbflra", F),  -- GNAT.MBBS_Float_Random

gcc/testsuite/ChangeLog

 2018-08-21  Hristian Kirtchev  <kirtchev@adacore.com>
 
+	* gnat.dg/linkedlist.adb: New testcase.
+
+2018-08-21  Hristian Kirtchev  <kirtchev@adacore.com>
+
 	* gnat.dg/elab6.adb, gnat.dg/elab6.ads, gnat.dg/elab6_pkg.adb,
 	gnat.dg/elab6_pkg.ads: New testcase.