* README: --gc-sections and map files are now supported. Document

some build requirements.

gold/ChangeLog

@@ -1,5 +1,8 @@
 2009-02-28  Ian Lance Taylor  <iant@google.com>
 
+	* README: --gc-sections and map files are now supported.  Document
+	some build requirements.
+
 	PR 6992
 	* symtab.cc (Symbol_table::sized_write_section_symbol): In a
 	relocatable link set the value of the section symbol to zero.

gold/README

@@ -17,9 +17,7 @@ omissions--features of the GNU linker not currently supported in
 gold--are:
   * MEMORY regions in linker scripts
   * MRI compatible linker scripts
-  * linker map files (-M, -Map)
   * cross-reference reports (--cref)
-  * linker garbage collection (--gc-sections)
   * position independent executables (-pie)
   * various other minor options
 
@@ -51,3 +49,16 @@ of work.  Task objects are stored on a single Workqueue object.  Tasks
 communicate via Task_token objects.  Task_token objects are only
 manipulated while holding the master Workqueue lock.  Relatively few
 mutexes are used.
+
+
+Build requirements
+==================
+
+The gold source code uses templates heavily.  Building it requires a
+recent version of g++.  g++ 4.0.3 is known to work.  g++ 3.2 and g++
+3.4.3 are known to fail.
+
+The linker script parser uses features which are only in newer
+versions of bison.  bison 2.3 is known to work.  bison 1.26 is known
+to fail.  If you are building gold from an official binutils release,
+the bison output should already be included.