gcc.texi (G++ and GCC): Mention Ada front end.

	* doc/gcc.texi (G++ and GCC): Mention Ada front end.
	(Standards): Refer to GNAT Reference Manual.

	* doc/install.texi (Configuration): Mention Ada front end.
	(Building): Add build instructions for the Ada front end.

	* doc/invoke.texi (Overall Options): Document Ada file types.
	Add "ada" to "-x LANGUAGE" option parameters.

From-SVN: r46479

gcc/doc/gcc.texi

@@ -296,16 +296,17 @@ bugs.  It corresponds to GCC version 3.1.
 
 @ifset USING
 @node G++ and GCC
-@chapter Compile C, C++, Objective-C, Fortran, Java or CHILL
+@chapter Compile C, C++, Objective-C, Ada, CHILL, Fortran, or Java
 
 @cindex Objective-C
 @cindex Fortran
 @cindex Java
 @cindex CHILL
-Several versions of the compiler (C, C++, Objective-C, Fortran, Java
-and CHILL) are integrated; this is why we use the name
+@cindex Ada
+Several versions of the compiler (C, C++, Objective-C, Ada, CHILL,
+Fortran, and Java) are integrated; this is why we use the name
 ``GNU Compiler Collection''.  GCC can compile programs written in any of these
-languages.  The Fortran, CHILL, and Java compilers are described in
+languages.  The Ada, CHILL, Fortran, and Java compilers are described in
 separate manuals.
 
 @cindex GCC
@@ -321,12 +322,17 @@ When referring to C++ compilation, it is usual to call the compiler
 it ``GCC'' no matter what the language context; however, the term
 ``G++'' is more useful when the emphasis is on compiling C++ programs.
 
+@cindex Ada
+@cindex GNAT
+Similarly, when we talk about Ada compilation, we usually call the
+compiler ``GNAT'', for the same reasons.
+
 We use the name ``GCC'' to refer to the compilation system as a
 whole, and more specifically to the language-independent part of the
 compiler.  For example, we refer to the optimization options as
 affecting the behavior of ``GCC'' or sometimes just ``the compiler''.
 
-Front ends for other languages, such as Ada 95 and Pascal exist but
+Front ends for other languages, such as Mercury and Pascal exist but
 have not yet been integrated into GCC@.  These front ends, like that for C++,
 are built in subdirectories of GCC and link to it.  The result is an
 integrated compiler that can compile programs written in C, C++,
@@ -513,15 +519,19 @@ recent version, while @uref{http://www.toodarkpark.org/computers/objc/}
 is an older example.  @uref{http://www.gnustep.org} includes useful
 information as well.
 
+@xref{Top, GNAT Reference Manual, About This Guide, gnat_rm, 
+GNAT Reference Manual}, for information on standard
+conformance and compatibility of the Ada compiler.
+
+@xref{References,,Language Definition References, chill, GNU Chill},
+for details of the CHILL standard.
+
 @xref{Language,,The GNU Fortran Language, g77, Using and Porting GNU
 Fortran}, for details of the Fortran language supported by GCC@.
 
 @xref{Compatibility,,Compatibility with the Java Platform, gcj, GNU gcj},
 for details of compatibility between @code{gcj} and the Java Platform.
 
-@xref{References,,Language Definition References, chill, GNU Chill},
-for details of the CHILL standard.
-
 @include invoke.texi
 
 @include install-old.texi

gcc/doc/install.texi

@@ -632,9 +632,10 @@ their runtime libraries should be built.  For a list of valid values for
 grep language= */config-lang.in
 @end example
 Currently, you can use any of the following:
-@code{c}, @code{c++}, @code{f77}, @code{java} and @code{objc}.
+@code{ada}, @code{c}, @code{c++}, @code{f77}, @code{java}, @code{objc}.
 @code{CHILL} is not currently maintained, and will almost
-certainly fail to compile.@*
+certainly fail to compile.  Building the Ada compiler has special
+requirements, see below.@*
 If you do not pass this flag, all languages available in the @file{gcc}
 sub-tree will be configured.  Re-defining @code{LANGUAGES} when calling
 @samp{make bootstrap} @strong{does not} work anymore, as those
@@ -764,7 +765,8 @@ Now that GCC is configured, you are ready to build the compiler and
 runtime libraries.
 
 We @strong{highly} recommend that GCC be built using GNU make;
-other versions may work, then again they might not.
+other versions may work, then again they might not.  
+GNU make is required for compiling GNAT, the Ada compiler.
 
 (For example, many broken versions of make will fail if you use the
 recommended setup where @var{objdir} is different from @var{srcdir}.
@@ -921,6 +923,56 @@ when building GCC@.  You can use a bigger number instead of two if
 you like.  In most cases, it won't help to use a number bigger than
 the number of processors in your machine.
 
+@section Building the Ada compiler
+
+In order to build GNAT, the Ada compiler, you need a working GNAT
+compiler, since the Ada front end is written in Ada (with some
+GNAT-specific extensions), and GNU make.
+
+However, you do not need a full installation of GNAT, just the GNAT
+binary @file{gnat1}, a copy of @file{gnatbind}, and a compiler driver
+which can deal with Ada input (by invoking the @file{gnat1} binary).
+You can specify this compiler driver by setting the @env{ADAC}
+environment variable at the configure step.  @command{configure} can
+detect the driver automatically if it has got a common name such as
+@command{gcc} or @command{gnatgcc}.  Of course, you still need a working
+C compiler (the compiler driver can be different or not).
+
+Additional build tools (such as @command{gnatmake}) or a working GNAT
+run-time library installation are usually @emph{not} required.  However,
+if you want to boostrap the compiler using a minimal version of GNAT,
+you have to issue the following commands before invoking @samp{make
+boostrap} (this assumes that you start with an unmodified and consistent
+source distribution):
+
+@example
+    cd @var{srcdir}/gcc/ada
+    touch treeprs.ads [es]info.h nmake.ad[bs]
+@end example
+
+At the moment, the GNAT library and several tools for GNAT are not built
+by @samp{make bootstrap}.  You have to invoke 
+@samp{make gnatlib_and_tools} in the @file{@var{objdir}/gcc}
+subdirectory before proceeding with the next steps.
+
+For example, you can build a native Ada compiler by issuing the
+following commands (assuming @command{make} is GNU make):
+
+@example
+    cd @var{objdir}
+    @var{srcdir}/configure --enable-languages=c,ada 
+    cd @var{srcdir}/gcc/ada
+    touch treeprs.ads [es]info.h nmake.ad[bs]
+    cd @var{objdir}    
+    make bootstrap
+    cd gcc
+    make gnatlib_and_tools
+    cd ..
+@end example
+
+Currently, when compiling the Ada front end, you cannot use the parallel
+build feature described in the previous section.
+
 @html
 <hr>
 <p>

gcc/doc/invoke.texi

@@ -706,11 +706,18 @@ Fortran input files.
 @c @var{file}.zip
 @c @var{file}.jar
 
+@item @var{file}.ads
+Ada source code file which contains a library unit declaration (a
+declaration of a package, subprogram, or generic, or a generic
+instantiation), or a library unit renaming declaration (a package,
+generic, or subprogram renaming declaration).  Such files are also
+called @dfn{specs}.
+
+@itemx @var{file}.adb
+Ada source code file containing a library unit body (a subprogram or
+package body).  Such files are also called @dfn{bodies}.
+
 @c GCC also knows about some suffixes for languages not yet included:
-@c Ada:
-@c @var{file}.ads
-@c @var{file}.adb
-@c @var{file}.ada
 @c Pascal:
 @c @var{file}.p
 @c @var{file}.pas
@@ -744,8 +751,10 @@ c  c-header  cpp-output
 c++  c++-cpp-output
 objective-c  objc-cpp-output
 assembler  assembler-with-cpp
+ada
+chill
 f77  f77-cpp-input  ratfor
-java  chill
+java
 @end example
 @c Also f77-version, for internal use only.