Re: Compiling FSF GNAT standalone?

[Simon Wright <simon@pushface.org>]

Patrick <patrick@spellingbeewinnars.org> writes:

> If I call gnatmake, it will call GCC eventually, so I supposed the
> term freestanding GNAT is false. However if I call gnatpp then it is
> not going to call GCC and there is no way to call gnatpp from GCC so I
> guess GNAT is not completely dependent on GCC. I would like to build
> GNAT from source to be able to call gnatpp. I thought it would also be
> interesting to try to compile it with a cross compiler so that it
> could be used on other architectures.

gnatpp is an application written in Ada using AdaCore's ASIS
implementation.

GNAT's ASIS is (a) a library which provides access to information about
source programs which can be output by the front-end of the GNAT
compiler, (b) a set of tools built to use ASIS to allow various kinds of
processing on source programs. gnatpp is one of these.

gnatpp's source is not part of the GCC source tree, ie not part of FSF
GCC, any more than GNAT ASIS is. You have access to the source for both
as part of the GNAT GPL distribution: look under ASIS. You ought to be
able to build GNAT GPL 2012 ASIS (library and tools) using the GNAT GPL
2012 compiler.

The compiler and ASIS are highy coupled, so building GNAT GPL 2012 ASIS
using the Debian compiler suite requires workrounds (I wrote about this,
for Mac OS X & GCC 4.6, at [1]); but I see that Debian 6 has various ASIS
packages, including asis-programs, which includes gnatpp.

gnatpp is not called from GCC. It can be called from GPS (again, not
part of GCC).

[1] http://forward-in-code.blogspot.co.uk/2011/10/building-asis.html