\input texinfo   @c -*-texinfo-*-
@c %**start of header
@setfilename make.info
@settitle GNUstep Makefile Package
@c %**end of header

@setcontentsaftertitlepage
@smallbook
@setchapternewpage odd

@ifinfo

Copyright @copyright{}  2000 Free Software Foundation, Inc.
   
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation.

@end ifinfo

@titlepage

@title GNUstep Makefile Package

@page

@vskip 0pt plus 1filll
Copyright @copyright{}  2000 Free Software Foundation, Inc.

@sp 1   
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation.

@end titlepage
@page

@c Makefile Package Chapter
@node Top, Makefile Introduction, (dir), (dir)
@chapter Makefile Package

@menu
* Makefile Introduction::       
* Makefile Structure::          
* Running Make::                
* GNUmakefile.preamble::        
* GNUmakefile.postamble::       
* Project Types::               
* Common Variables::            
@end menu

@node Makefile Introduction, Makefile Structure, Top, Top
@section Introduction

The Makefile package is a system of make commands that is designed to
encapsulate all the complex details of building and installing various types
of projects from libraries to applications to documentation. This frees the
developer to focus on the details of their particular project. Only
a fairly simple main makefile need to be written which specifies the
type of project and files involved in the project.

@node Makefile Structure, Running Make, Makefile Introduction, Top
@section Structure of a Makefile

Here is an example makefile (named GNUmakefile to emphasis the fact that it relies on special features of the GNU make program).

@smallexample
#
# An example GNUmakefile
#

# Include the common variables defined by the Makefile Package
include $(GNUSTEP_MAKEFILES)/common.make

# Build a simple Objective-C program
OBJC_PROGRAM_NAME = simple

# The Objective-C files to compile
simple_OBJC_FILES = simple.m

-include GNUmakefile.preamble

# Include in the rules for making Objective-C programs
include $(GNUSTEP_MAKEFILES)/objc.make

-include GNUmakefile.postamble
@end smallexample

This is all that is necessary to define the project.


@node Running Make, GNUmakefile.preamble, Makefile Structure, Top
@section Running Make
@menu
* Debug Information::           
* Profile Information::         
* Library Types::               
@end menu

Normally to compile a package which uses the Makefile Package it is
purely a matter of typing @code{make} from the top-level directory of
the package, and the package is compiled without any additional
interaction.  

@node Debug Information, Profile Information, Running Make, Running Make
@subsection Debug Information

By default the Makefile Package does not tell the compiler to generate
debugging information when compiling Objective-C and C files.  The
following command illustrates how to tell the Makefile Package to pass
the appropriate flags to the compiler so that debugging information is
put into the binary files.

@smallexample
make debug=yes
@end smallexample

When debugging is turned on, the Makefile Package turns off optimization
so the user must override the optimization flag when running make if
both debugging information and optimization is to be performed by the
compiler. Use the variable @var{OPTFLAG} to override the
optimization flag.

@node Profile Information, Library Types, Debug Information, Running Make
@subsection Profile Information

By default the Makefile Package does not tell the compiler to generate
profiling information when compiling Objective-C and C files.  The
following command illustrates how to tell the Makefile Package to pass
the appropriate flags to the compiler so that profiling information is
put into the binary files.

@smallexample
make profile=yes
@end smallexample

@node Library Types,  , Profile Information, Running Make
@subsection Static, Shared, and Dynamic Link Libraries

By default the Makefile Package will generate a shared library if it is
building a library project type, and it will link with shared libraries
if it is building an application or command line tool project type.  The
following command illustrates how to tell the Makefile Package not to
build using shared libraries but using static libraries instead.

@smallexample
make shared=no
@end smallexample

This default is only applicable on systems that support shared
libraries; systems that do not support shared libraries will always
build using static libraries.  Some systems support dynamic link
libraries (DLL) which are a form of shared libraries; on these systems,
DLLs will be built by default unless the Makefile Package is told to
build using static libraries instead, as in the above command.

@node Project Types, Common Variables, GNUmakefile.postamble, Top
@section Project Types
@menu
* aggregate.make::              
* application.make::            
* bundle.make::                 
* ctool.make::                  
* documentation.make::          
* framework.make::              
* java.make::                   
* library.make::                
* native-library.make::                
* objc.make::                   
* palette.make::                
* rpm.make::                    
* service.make::                
* subproject.make::             
* tool.make::                   
@end menu

Projects are divided into different types described below. To create a
project of a specific type, just include the particular makefile. For
example, to create an application, include this line in your make make
file:

@example
include $(GNUSTEP_MAKEFILES)/application.make
@end example

Each project type is independent of the others. If you want to create
two different types of projects within the same directory (e.g. a tool
and a java program), include both the desired makefiles in your main
make file.

@node aggregate.make, application.make, Project Types, Project Types
@subsection Aggregate (@file{aggregate.make})

An Aggregate project is a project that consists of several
subprojects. Each subproject can be of any other valid project type
(including the Aggregate type). The only project variable is the
SUBPROJECTS variable

@defvr {Aggregate project} SUBPROJECTS
@code{SUBPROJECTS} defines the directory names that hold the subprojects
that the Aggregate project should build.
@end defvr

@node application.make, bundle.make, aggregate.make, Project Types
@subsection Graphical Applications (@file{application.make})

An application is an Objective-C program that includes a GUI component,
and by default links in all the GNUstep libraries required for GUI
development, such as the Base and Gui libraries.

@node bundle.make, ctool.make, application.make, Project Types
@subsection Bundles (@file{bundle.make})

A bundle is a collection of resources and code that can be used to
enhance an existing application or tool dynamically using the NSBundle
class from the GNUstep base library.

@node ctool.make, documentation.make, bundle.make, Project Types
@subsection Command Line C Tools (@file{ctool.make})

A ctool is a project that only uses C language files.
Otherwise it is similar to the ObjC project type.

@node documentation.make, framework.make, ctool.make, Project Types
@subsection Documentation (@file{documentation.make})

The Documentation project provides rules to use various types of
documentation such as texi and LaTeX documentation, and convert them
into finished documentation (info, PostScript, HTML, etc). 

@node framework.make, java.make, documentation.make, Project Types
@subsection Frameworks (@file{framework.make})

A Framework is a collection of resources and a library that provides
common code that can be linked into a Tool or Application. In many
respects it is similar to a Bundle.

@node java.make, library.make, framework.make, Project Types
@subsection Java (@file{java.make})

This project provides rules for building java programs. It also makes it
easy to make java projects that interact with the GNUstep libraries.

@node library.make, native-library.make, java.make, Project Types
@subsection Libraries (@file{library.make})
@menu
* library.make variables::      
* Example Library Makefile::    
@end menu

The Makefile Package provides a project type for building libraries;
libraries can be built as static libraries, shared libraries, or dynamic
link libraries (DLL) if the platform supports that type of library.
Static libraries are supported on all platforms; while, shared libraries
and DLLs are only supported on some platforms.

@node library.make variables, Example Library Makefile, library.make, library.make
@subsubsection Project Variables

@defvr {Library project} LIBRARY_NAME
@code{LIBRARY_NAME} should be assigned the list of name of libraries to
be generated.  Most UNIX systems expect that the filename for the
library has the word @file{lib} prefixed to the name; i.e. the @file{c}
library has filename of @file{libc}.  Prefix the @file{lib} to the
library name when it is specified in the @code{LIBRARY_NAME} variable
because the Makefile Package will not automatically prefix it.
@end defvr

@defvr {Library project} C_FILES
@code{xxx_C_FILES} is the list of C files, with a @file{.c} extension,
that are to be compiled to generate the @strong{xxx} library.
Replace the @strong{xxx} with the name of the library as listed by
the @code{LIBRARY_NAME} variable.
@end defvr

@defvr {Library project} OBJC_FILES
@code{xxx_OBJC_FILES} is the list of Objective-C files, with a @file{.m}
extension, that are to be compiled to generate the @strong{xxx} library.
Replace the @strong{xxx} with the name of the library as listed by the
@code{LIBRARY_NAME} variable.
@end defvr

@defvr {Library project} PSWRAP_FILES
@code{xxx_PSWRAP_FILES} is the list of PostScript wrap files, with a
@file{.psw} extension, that are to be compiled to generate the
@strong{xxx} library.  PostScript wrap files are processed by the
@file{pswrap} utility which generates a @file{.c} and a @file{.h} file
from each @file{.psw} file; the generate @file{.c} file is the file
actually compiled.  Replace the @strong{xxx} with the name of the
library as listed by the @code{LIBRARY_NAME} variable.
@end defvr

@defvr {Library project} HEADER_FILES
@code{xxx_HEADER_FILES} is the list of header filenames that are to be
installed with the library.  If a filename has a directory path prefixed
to it then that prefix will be maintained when the headers are
installed.  It is up to the user to make sure that the installation
directory exists; otherwise, an error will occur when the library is
installed, see @ref{library.make
variables,,xxx_HEADER_FILES_INSTALL_DIR}.  Replace the @strong{xxx} with
the name of the library as listed by the @code{LIBRARY_NAME} variable.
@end defvr

@defvr {Library project} HEADER_FILES_DIR
@code{xxx_HEADER_FILES_DIR} is the relative path from the current
directory, where the makefile is located, to where the header files
specified by @code{xxx_HEADER_FILES} are located.  If a filename
specified in @code{xxx_HEADER_FILES} has a directory path prefixed to it
then that path will not be removed when the Makefile Package accesses
the files, so do not specify a path with @code{xxx_HEADER_FILES_DIR}
that is already prefixed to the header filenames, see @ref{library.make
variables,,xxx_HEADER_FILES_INSTALL_DIR}.  @code{xxx_HEADER_FILES_DIR}
is optional; leaving it blank or undefined, and the Makefile Package
assumes that the relative path to the header files is the current
directory where the makefile resides.  Replace the @strong{xxx} with the
name of the library as listed by the @code{LIBRARY_NAME} variable.
@end defvr

@defvr {Library project} HEADER_FILES_INSTALL_DIR
@code{xxx_HEADER_FILES_INSTALL_DIR} specifies the relative subdirectory
path below @code{GNUSTEP_HEADERS} where the header files are to be
installed.  If this directory or any of its parent directories do not
exist, then the Makefile Package will create them.  The Makefile Package
prefixes @code{xxx_HEADER_FILES_INSTALL_DIR} to each of the filenames in
@code{xxx_HEADER_FILES} when they are installed, so if the filenames in
@code{xxx_HEADER_FILES} already have a directory path prefixed then the
user is responsible for creating that directory, the Makefile Package
will not create.  @code{xxx_HEADER_FILES_INSTALL_DIR} is optional;
leaving it blank or undefined, and the Makefile Package assumes that the
installation directory is just @code{GNUSTEP_HEADERS} with no
subdirectory.  Replace the @strong{xxx} with the name of the library as
listed by the @code{LIBRARY_NAME} variable.
@end defvr

@defvr {Library project} CPPFLAGS
@code{xxx_CPPFLAGS} are additional flags that will be passed to the
compiler preprocessor when compiling Objective-C and C files to generate
the @strong{xxx} library.  Adding flags here does not override the
default @code{CPPFLAGS}, see @ref{Overridable Flags,,CPPFLAGS}, they are
in addition to @code{CPPFLAGS}.  These flags are specific to the
@strong{xxx} library, see @ref{GNUmakefile.preamble,,ADDITIONAL_CPPFLAGS},
to see how to specify global preprocessor flags.  Replace the
@strong{xxx} with the name of the listed as listed by the
@code{LIBRARY_NAME} variable.
@end defvr

@defvr {Library project} OBJCFLAGS
@code{xxx_OBJCFLAGS} are additional flags that will be passed to the
compiler when compiling Objective-C files to generate the @strong{xxx}
library.  Adding flags here does not override the default
@code{OBJCFLAGS}, see @ref{Overridable Flags,,OBJCFLAGS}, they are in
addition to @code{OBJCFLAGS}.  These flags are specific to the
@strong{xxx} library, see @ref{GNUmakefile.preamble,,ADDITIONAL_OBJCFLAGS},
to see how to specify global compiler flags.  Replace the @strong{xxx}
with the name of the library as listed by the @code{LIBRARY_NAME}
variable.
@end defvr

@defvr {Library project} CFLAGS
@code{xxx_CFLAGS} are additional flags that will be passed to the
compiler when compiling C files to generate the @strong{xxx} library.
Adding flags here does not override the default @code{CFLAGS}, see
@ref{Overridable Flags,,CFLAGS}, they are in addition to @code{CFLAGS}.
These flags are specific to the @strong{xxx} library, see
@ref{GNUmakefile.preamble,,ADDITIONAL_CFLAGS}, to see how to specify global
compiler flags.  Replace the @strong{xxx} with the name of the library
as listed by the @code{LIBRARY_NAME} variable.
@end defvr

@defvr {Library project} LDFLAGS
@code{xxx_LDFLAGS} are additional flags that will be passed to the
linker when it creates the @strong{xxx} library.  Adding flags here does
not override the default @code{LDFLAGS}, see @ref{Overridable
Flags,,LDFLAGS}, they are in addition to @code{LDFLAGS}.  These flags
are specific to the @strong{xxx} library, see
@ref{GNUmakefile.preamble,,ADDITIONAL_LDFLAGS}, to see how to specify
global linker flags.  Replace the @strong{xxx} with the name of the
library as listed by the @code{LIBRARY_NAME} variable.
@end defvr

@defvr {Library project} INCLUDE_DIRS
@code{xxx_INCLUDE_DIRS} is the list of additional directories that the
compiler will search when it is looking for include files; these flags
are specific to the @strong{xxx} library, see
@ref{GNUmakefile.preamble,,ADDITIONAL_INCLUDE_DIRS}, to see how to specify
additional global include directories.  The directories should be
specified as @samp{-I} flags to the compiler.  The additional include
directories will be placed before the normal GNUstep and system include
directories, and before any global include directories specified with
@code{ADDITIONAL_INCLUDE_DIRS}, so they will always be searched first.
Replace the @strong{xxx} with the name of the library as listed by the
@code{LIBRARY_NAME} variable.
@end defvr

@node Example Library Makefile,  , library.make variables, library.make
@subsubsection Example Makefile

This example makefile illustrates two libraries, @file{libone} and
@file{libtwo}, that are to be generated.

@smallexample

#
# An example makefile
#

# Include the common variables defined by the Makefile Package
include $(GNUSTEP_MAKEFILES)/common.make

# Two libraries
LIBRARY_NAME = libone libtwo

#
# The files for the libone library
#
# The Objective-C files to compile
libone_OBJC_FILES = one.m draw.m

# The C source files to be compiled
libone_C_FILES = parse.c

# The PostScript wrap source files to be compiled
libone_PSWRAP_FILES = drawing.psw

# The header files for the library
libone_HEADER_FILES_DIR = ./one
libone_HEADER_FILES_INSTALL_DIR = one
libone_HEADER_FILES = one.h draw.h

#
# The files for the libtwo library
#
# The Objective-C files to compile
libtwo_OBJC_FILES = two.m another.m test.m

# The header files for the library
libtwo_HEADER_FILES_DIR = ./two
libtwo_HEADER_FILES_INSTALL_DIR = two
libtwo_HEADER_FILES = two.h another.h test.h common.h

# Option include to set any additional variables
-include GNUmakefile.preamble

# Include in the rules for making libraries
include $(GNUSTEP_MAKEFILES)/library.make

# Option include to define any additional rules
-include GNUmakefile.postamble

@end smallexample

Notice that the @file{libone} library has Objective-C, C, and PostScript
wrap files to be compiled; while, the @file{libtwo} library only has
some Objective-C files.

The header files for the @file{libone} library reside in the @file{one}
subdirectory from where the sources are located, and the header files
will be installed into the @file{one} subdirectory within
@code{GNUSTEP_HEADERS}.  Likewise the header files for the @file{libtwo}
library reside in the @file{two} subdirectory from where the sources are
located, and the header files will be installed into the @file{two}
subdirectory within @code{GNUSTEP_HEADERS}.

@node native-library.make, objc.make, library.make, Project Types
@subsection Native Library (@file{native-library.make})

A "native library" is a project which is to be built as a shared
library on most targets and as a framework on Darwin.  (Currently
this is only the case for apple-apple-apple.)  In other
words, it is to be built as the most appropriate native equivalent
of a traditional shared library (see @ref{library.make} and
@ref{framework.make}).

@defvr {Native Library project} NATIVE_LIBRARY_NAME
@code{NATIVE_LIBRARY_NAME} should be the name of the native library,
without the 'lib'.  All the other variables are the same as
the ones used in libraries and frameworks.
@end defvr

To compile something against a native library, you can use
@code{ADDITIONAL_NATIVE_LIBS += MyLibrary}
This will be converted into -lMyLibrary link flag on for most
targets and into -framework MyLibrary link flag for
apple-apple-apple.

@node objc.make, palette.make, native-library.make, Project Types
@subsection Objective-C Programs (@file{objc.make})
@menu
* objc.make variables::         
* Example ObjC Makefile::       
@end menu

The Makefile Package provides a project type that is useful for building
Objective-C programs that do not depend upon the GNUstep libraries.
Objective-C programs which only use the Objective-C Runtime Library and
the classes it defines are candidates for this project type.

@node objc.make variables, Example ObjC Makefile, objc.make, objc.make
@subsubsection Project Variables

Most of the project variables work the same as in Library
projects (see @ref{library.make}).

@defvr {Objective-C program project} OBJC_PROGRAM_NAME
@code{OBJC_PROGRAM_NAME} is the list of names of Objective-C programs
that are to be built; each name should be unique as it is the name of
the executable file that will be generated.
@end defvr

@defvr {Objective-C program project} OBJC_LIBS
@code{xxx_OBJC_LIBS} is the list of additional libraries that the linker
will use when linking to create the @strong{xxx} Objective-C program
executable file.  These libraries are specific to the @strong{xxx}
Objective-C program, see @ref{GNUmakefile.preamble,,ADDITIONAL_OBJC_LIBS},
to see how to specify additional global libraries.  These libraries are
placed before all of the Objective-C Runtime and system libraries, and
before the global libraries specified with @code{ADDITIONAL_OBJC_LIBS},
so that they will be searched first when linking.  The additional
libraries should be specified as @samp{-l} flags to the linker as the
following example illustrates.  Replace the @strong{xxx} with the name
of the program as listed by the @code{OBJC_PROGRAM_NAME} variable.
@end defvr

@node Example ObjC Makefile,  , objc.make variables, objc.make
@subsubsection Example Makefile

This makefile illustrates two Objective-C programs, @file{simple} and
@file{list} that are to be generated.

@smallexample
#
# An example makefile
#

# Include the common variables defined by the Makefile Package
include $(GNUSTEP_MAKEFILES)/common.make

# Build a simple Objective-C program
OBJC_PROGRAM_NAME = simple list

# Have the Objective-C runtime macro be defined for simple program
simple_CPPFLAGS = $(RUNTIME_DEFINE)

# The Objective-C files to compile for simple program
simple_OBJC_FILES = simple.m

# The Objective-C files to compile for list program
list_OBJC_FILES = list.m linkedlist.m

# The C files to compile for list program
list_C_FILES = sort.c

# Option include to set any additional variables
-include GNUmakefile.preamble

# Include in the rules for making Objective-C programs
include $(GNUSTEP_MAKEFILES)/objc.make

# Option include to define any additional rules
-include GNUmakefile.postamble
@end smallexample

The @file{simple} Objective-C program only consists of single
Objective-C file; while, the @file{list} Objective-C program consists of
two Objective-C files and one C file.  The @file{simple} Objective-C
program use the variable defined by the Makefile Package,
@code{RUNTIME_DEFINE}, to define a macro based upon the Objective-C
Runtime library; presumably @file{simple.m} has code which is dependent
upon the Objective-C Runtime.

@node palette.make, rpm.make, objc.make, Project Types
@subsection Palettes (@file{palette.make})

A palette is a Bundle that provides some kind of GUI functionality.
Otherwise it is similar to the Bundle project.

@node rpm.make, service.make, palette.make, Project Types
@subsection RPMs (@file{rpm.make})

The RPM project provides rules for automatically generating RPM spec
files in order to make RPM distributions. Note that this project
makefile is included automatically when you include any other project
type in your GNUmakefile. It is non necessary to include
@file{rpm.make}.

Except for @code{PACKAGE_NAME}, which is required, all the following
variables are optional. It is recommended that you set them anyway in
order to provide the standard information that is present in most RPM
distributions.

@defvr {RPM} PACKAGE_NAME
@code{PACKAGE_NAME} defines the name of the RPM distribution. In most
cases this will be the same as the name of your project type. For
instance, if you are creating a application, and have set
@code{APP_NAME} to @samp{MyApplication}, Then set @code{PACKAGE_NAME} to
the same thing, or just use @code{PACKAGE_NAME=$(APP_NAME)}.  if 
@code{PACKAGE_NAME} is not set, it defaults to @code{unnamed-package}
@end defvr

@defvr {RPM} PACKAGE_VERSION
Set @code{PACKAGE_VERSION} to the release version number of your package. If not
set, it defaults to 0.0.1
@end defvr

@defvr {RPM} GNUSTEP_INSTALLATION_DIR
Set @code{GNUSTEP_INSTALLATION_DIR} to the installation
directory. Typically this is either @code{$(GNUSTEP_SYSTEM_ROOT)}),
@code{$(GNUSTEP_LOCAL_ROOT)}, or @code{$(GNUSTEP_USER_ROOT)}. If not set
it defaults to @code{$(GNUSTEP_LOCAL_ROOT)}.
@end defvr

@defvr {RPM} RPM_DISABLE_RELOCATABLE
Set this to @code{YES} if the package must be in @code{$(GNUSTEP_SYSTEM_ROOT)}
and is not relocatable.
@end defvr

@defvr {RPM} PACKAGE_NEEDS_CONFIGURE
Set this to @code{YES} if a configure script needs to be run before
compilation
@end defvr

In addition you need to provide a stub spec file named for the package
name, such as this example @file{libobjc.spec.in} file:

@example
Release:        1
Source:         ftp://ftp.gnustep.org/pub/gnustep/libs/%@{gs_name@}-%@{gs_version@}.
tar.gz
Copyright:      GPL
Group:          Development/Libraries
Summary:        Objective-C Runtime Library
Packager:       Adam Fedor <fedor@@gnu.org>
Vendor:         The GNUstep Project
URL:            http://www.gnustep.org/

%description
Library containing the Objective-C runtime.
@end example

@node service.make, subproject.make, rpm.make, Project Types
@subsection Services (@file{service.make})

A Service is like a Tool that provides a service to a running GNUstep program.

@node subproject.make, tool.make, service.make, Project Types
@subsection Subprojects (@file{subproject.make})

A Subproject provides a way to organize code in a large application into
subunits. The code in the subproject is merged in with the main tool
or application.

@node tool.make,  , subproject.make, Project Types
@subsection Command Line Tools (@file{tool.make})

A tool is an ObjC project that by default links in the GNUstep base
library. Otherwise it is similar to the ObjC project type.

@node GNUmakefile.preamble, GNUmakefile.postamble, Running Make, Top
@section Global Variables (@file{GNUmakefile.preamble})

@file{GNUmakefile.preamble} is an optional file that may be put within the
package for declaring global makefile variables for the package.  The
filename, @file{GNUmakefile.preamble}, is just a convention; likewise, the
variables defined within it can be put in the normal @file{GNUmakefile}
versus in this special file.  However, the reason for this convention is
that the @file{GNUmakefile} may be automatically maintained by a project
management system, like Project Center, so any changes made to
@file{GNUmakefile} may be discarded by that project management system.

The file, @file{GNUmakefile.preamble}, in the Makefile Package is a
template that can be used the project's @file{GNUmakefile.preamble}.  It is
not necessary to have a @file{GNUmakefile.preamble} with the project unless
it is actually needed, the Makefile Package will only include it if it
is available, see @ref{Makefile Structure} for information on how the
Makefile Package includes a @file{GNUmakefile.preamble}.

The rest of this section describes the individual global variables that
the Makefile Package uses which are generally placed in the package's
@file{GNUmakefile.preamble}.

@defvar ADDITIONAL_CPPFLAGS
@code{ADDITIONAL_CPPFLAGS} are additional flags that will be passed to
the compiler preprocessor.  Generally any macros to be defined for all
files are placed here; the are passed for both Objective-C and C files
that are compiled.  @code{RUNTIME_DEFINE}, @code{FOUNDATION_DEFINE},
@code{GUI_DEFINE}, and @code{GUI_BACKEND_DEFINE} are some makefile
variables which define macros that can be assigned to
@code{ADDITIONAL_CPPFLAGS}.  The following example illustrates the use
of @code{ADDITIONAL_CPPFLAGS} to define a macro for the Objective-C
Runtime Library plus an additional macro that is specific to the
package.
@end defvar

@smallexample
ADDITIONAL_CPPFLAGS = $(RUNTIME_DEFINE) -DVERBOSE=1
@end smallexample

@defvar ADDITIONAL_OBJCFLAGS
@code{ADDITIONAL_OBJCFLAGS} are additional flags that will be passed to
the compiler when compiling Objective-C files.  Adding flags here does
not override the default @code{OBJCFLAGS}, see @ref{Overridable
Flags,,OBJCFLAGS}, they are in addition to @code{OBJCFLAGS}.  Generally
@code{ADDITIONAL_OBJCFLAGS} are placed before @code{OBJCFLAGS} when the
compiler is executed, but one should avoid having any placement
sensitive flags because the order of the flags is not guaranteed.  The
following example illustrates how you can pass additional Objective-C
flags.
@end defvar

@smallexample
ADDITIONAL_OBJCFLAGS = -Wno-protocol
@end smallexample

@defvar ADDITIONAL_CFLAGS
@code{ADDITIONAL_CFLAGS} are additional flags that will be passed to the
compiler when compiling C files.  Adding flags here does not override
the default @code{CFLAGS}, see @ref{Overridable Flags,,CFLAGS}, they are
in addition to @code{CFLAGS}.  Generally @code{ADDITIONAL_CFLAGS} are
placed before @code{CFLAGS} when the compiler is executed, but one
should avoid having any placement sensitive flags because the order of
the flags is not guaranteed.  The following example illustrates how you
can pass additional C flags.
@end defvar

@smallexample
ADDITIONAL_CFLAGS = -finline-functions
@end smallexample

@defvar ADDITIONAL_LDFLAGS
@code{ADDITIONAL_LDFLAGS} are additional flags that will be passed to
the linker when it creates an executable; these flags are passed when
linking a command line tool, and application, or an Objective-C program.
Adding flags here does not override the default @code{LDFLAGS}, see
@ref{Overridable Flags,,LDFLAGS}, they are in addition to
@code{LDFLAGS}.  Generally @code{ADDITIONAL_LDFLAGS} are placed before
@code{LDFLAGS} when the linker is executed, but one should avoid having
any placement sensitive flags because the order of the flags is not
guaranteed.  The following example illustrates how you can pass addition
linker flags.
@end defvar

@smallexample
ADDITIONAL_LDFLAGS = -v
@end smallexample

@defvar ADDITIONAL_INCLUDE_DIRS
@code{ADDITIONAL_INCLUDE_DIRS} is the list of additional directories that
the compiler will search when it is looking for include files.  The
directories should be specified as @samp{-I} flags to the compiler.  The
additional include directories will be placed before the normal GNUstep
and system include directories, so they will always be searched first.
The following example illustrates two additional include directories;
@code{/usr/local/gnu/include} will be searched first, then
@code{/usr/gnu/include}, and finally the GNUstep and system directories
which are automatically defined by the Makefile Package.
@end defvar

@smallexample
ADDITIONAL_INCLUDE_DIRS = -I/usr/local/gnu/include -I/usr/gnu/include
@end smallexample

@defvar ADDITIONAL_LIB_DIRS
@code{ADDITIONAL_LIB_DIRS} is the list of additional directories that
the linker will search when it is looking for library files.  The
directories should be specified as @samp{-L} flags to the linker.  The
additional library directories will be placed before the GNUstep and
system library directories so that they will be searched first by the
linker.  The following example illustrates two additional library
directories; @code{/usr/local/gnu/lib} will be searched first, then
@code{/usr/gnu/lib}, and finally the GNUstep and system directories
which are automatically defined by the Makefile Package.
@end defvar

@smallexample
ADDITIONAL_LIB_DIRS = -L/usr/local/gnu/lib -L/usr/gnu/lib
@end smallexample

@defvar ADDITIONAL_OBJC_LIBS
@code{ADDITIONAL_OBJC_LIBS} is the list of additional libraries that the
linker will use when linking command line tools, applications, and
Objective-C programs, see @ref{tool.make}, @ref{application.make}, and
@ref{objc.make}.  For Objective-C programs, @code{ADDITIONAL_OBJC_LIBS}
is placed before all of the Objective-C Runtime and system libraries so
that they will be searched first when linking.  For command line tools
and applications, @code{ADDITIONAL_OBJC_LIBS} is placed @emph{before}
all of the Objective-C Runtime and system libraries but @emph{after} the
Foundation and GUI libraries.  Libraries specified with
@code{ADDITIONAL_OBJC_LIBS} should only depend upon the Objective-C
Runtime and/or system functions, not Foundation or GUI classes;
Foundation dependent libraries should be specified with
@code{ADDITIONAL_TOOL_LIBS} and GUI dependent libraries should be
specified with @code{ADDITONAL_GUI_LIBS}.  The additional libraries
should be specified as @samp{-l} flags to the linker as the following
example illustrates.
@end defvar

@smallexample
ADDITIONAL_OBJC_LIBS = -lSwarm
@end smallexample

@defvar ADDITIONAL_TOOL_LIBS
@code{ADDITIONAL_TOOL_LIBS} is the list of additional libraries that the
linker will use when linking command line tools and applications, see
@ref{tool.make} and @ref{application.make}.  For command line tools,
@code{ADDITIONAL_TOOL_LIBS} is placed before all of the GNUstep and
system libraries so that they will be searched first when linking.  For
applications, @code{ADDITIONAL_TOOL_LIBS} is placed before the
Foundation and system libraries but after the GUI libraries.  Libraries
specified with @code{ADDITIONAL_TOOL_LIBS} should only depend upon the
Foundation classes and/or system functions, not GUI classes; GUI
dependent libraries should be specified with @code{ADDITIONAL_GUI_LIBS}.
The additional libraries should be specified as @samp{-l} flags to the
linker as the following example illustrates.
@end defvar

@smallexample
ADDITIONAL_TOOL_LIBS = -lone -lsimple
@end smallexample

@defvar ADDITIONAL_GUI_LIBS
@code{ADDITIONAL_GUI_LIBS} is the list of additional libraries that the
linker will use when linking applications, see @ref{application.make}.
@code{ADDITIONAL_GUI_LIBS} is placed before all of the GUI, Foundation,
and system libraries so that they will be searched first when linking.
The additional libraries should be specified as @samp{-l} flags to the
linker as the following example illustrates.
@end defvar

@smallexample
ADDITIONAL_GUI_LIBS = -lMiscGui
@end smallexample

@defvar LIBRARIES_DEPEND_UPON
@code{LIBRARIES_DEPEND_UPON} is the set of libraries that the shared
library depends upon, see @ref{library.make} for more information about
building shared libraries; this variable is only relevant for library
project types.  On some platforms when a shared library is built, any
libraries which the object code in the shared library depends upon must
be linked in the generation of the shared library.  This is similar to
the process of linking an executable file like a command line tool or
Objective-C program except that the result is a shared library.
Libraries specified with @code{LIBRARIES_DEPEND_UPON} should be listed
as @samp{-l} flags to the linker; when possible use variables defined by
the Makefile Package to specify GUI, Foundation, or system libraries;
like @code{GUI_LIBS}, @code{FND_LIBS}, @code{OBJC_LIBS}, or
@code{SYSTEM_LIBS}.  @code{LIBRARIES_DEPEND_UPON} is independent of
@code{ADDITIONAL_OBJC_LIBS}, @code{ADDITIONAL_TOOL_LIBS}, and
@code{ADDITIONAL_GUI_LIBS}, so any libraries specified there may need to
be specified with @code{LIBRARIES_DEPEND_UPON}.  The following example
illustrates the use of @code{LIBRARIES_DEPEND_UPON} for a shared library
that is depend upon the Foundation, ObjC, system libraries and an
additional user library.
@end defvar

@smallexample
LIBRARIES_DEPEND_UPON = -lsimple $(FND_LIBS) $(OBJC_LIBS) $(SYSTEM_LIBS)
@end smallexample

@defvar ADDITIONAL_INSTALL_DIRS
@code{ADDITIONAL_INSTALL_DIRS} is the list of additional directories
that should be created when the Makefile Package installs the file for
the project.  These directories are only one that the project needs to
be created but that the Makefile Package does not automatically create.
The directories should be absolute paths but use the
@code{GNUSTEP_INSTALLATION_DIR} variable and other Makefile Package
define variables, see @ref{Directory Paths}, so that the directories get
created in the appropriate place relative to the other file installed
for the project.  The following example illustrates how two additional
directories can be created during installation.
@end defvar

@smallexample
ADDITIONAL_INSTALL_DIRS = $(GNUSTEP_INSTALLATION_DIR)/MyProject \
                          $(GNUSTEP_RESOURCES)/MyProject
@end smallexample

@node GNUmakefile.postamble, Project Types, GNUmakefile.preamble, Top
@section Global Rules (@file{GNUmakefile.postamble})

The @file{GNUmakefile.postamble} file is an optional file you may
include in your package to define additional rules that should be
executed when making and/or installing the project. There is a template
@file{GNUmakefile.postamble} file in the Makefile package that you can
use as an example. Most of the rules are self explanatory. The
@samp{before-} rules define things that should happen before a process
is executed (e.g. @samp{before-all} for before compilation,
@samp{before-install} for before installation). The @samp{after-} rules
define things that should happen after a process is complete.

You can even define additional rules such as ones that a particular to
your specific package or that are to be used by developers only.

@node Common Variables,  , Project Types, Top
@section Common Variables (@file{common.make})
@menu
* Directory Paths::             
* Scripts::                     
* Platform Information::        
* Library Combination::         
* Overridable Flags::           
@end menu


Any of these variables that are defined by @file{common.make} can and
should be used by the user's makefile fragments to reference directories
and/or perform any tasks which are not done automatically by the
Makefile Package.  Most variables refer to directory paths, both
absolute and relative, where files will be installed, but other
variables are defined based upon the target platform that the person is
compiling for.  Do not change the values of any of these automatically
defined variables as the resultant behaviour of the Makefile Package is
undefined.

@node Directory Paths, Scripts, Common Variables, Common Variables
@subsection Directory Paths

@defvar GNUSTEP_MAKEFILES
@code{GNUSTEP_MAKEFILES} is the absolute path to the directory where the
Makefile Package files are located.  Use @code{GNUSTEP_MAKEFILES} to
refer to a makefile fragment or script file from the Makefile Package
within a makefile; the @code{GNUSTEP_MAKEFILES} variable should be
only be used within makefiles and not referenced within C or Objective-C
programs.
@end defvar

@defvar GNUSTEP_APPS
@code{GNUSTEP_APPS} is the absolute path to the directory where GUI
applications are installed.  This variable is dependent upon the
@code{GNUSTEP_INSTALLATION_DIR} variable, so the path will change
accordingly if the user specifies a different installation root
directory.
@end defvar

@defvar GNUSTEP_TOOLS
@code{GNUSTEP_TOOLS} is the absolute path for the root directory where
command line tools are installed.  Only command line tools which are
target platform independent should be installed in @code{GNUSTEP_TOOLS};
target platform dependent command line tools should be placed in the
appropriate subdirectory of @code{GNUSTEP_TOOLS}, see @ref{Directory
Paths,,GNUSTEP_TARGET_DIR}, and @ref{Directory
Paths,,TOOL_INSTALLATION_DIR}.  This variable is dependent upon the
@code{GNUSTEP_INSTALLATION_DIR} variable, so the path will change
accordingly if the user specifies a different installation root
directory.
@end defvar

@defvar GNUSTEP_HEADERS
@code{GNUSTEP_HEADERS} is the absolute path for the root directory where
header files are installed.  Normally header files are not installed in
the @code{GNUSTEP_HEADERS} directory, but in a subdirectory as specified
by the project which owns the files, see @ref{library.make} for more
information.  @code{GNUSTEP_HEADERS} should contain platform independent
header files because the files are shared by all platforms.  Any target
platform dependent header files should be placed in the appropriate
subdirectory as specified by @code{GNUSTEP_TARGET_DIR}.  This variable
is dependent upon the @code{GNUSTEP_INSTALLATION_DIR} variable, so the
path will change accordingly if the user specifies a different
installation root directory.
@end defvar

@defvar GNUSTEP_LIBRARIES_ROOT
@code{GNUSTEP_LIBRARIES_ROOT} is the absolute path for the root
directory where libraries are installed.  Because libraries are binary
objects and thus inherently target platform dependent, no libraries
should actually reside in @code{GNUSTEP_LIBRARIES_ROOT}; libraries are
placed in the appropriate subdirectory taking the target and possibly
the library combo into account, see @ref{Directory
Paths,,GNUSTEP_TARGET_LIBRARIES}, and @ref{Directory
Paths,,GNUSTEP_LIBRARIES}.  This variable is dependent upon the
@code{GNUSTEP_INSTALLATION_DIR} variable, so the path will change
accordingly if the user specified a different installation root
directory.
@end defvar

@defvar GNUSTEP_TARGET_LIBRARIES
@code{GNUSTEP_TARGET_LIBRARIES} is the absolute path for the directory
where libraries are installed taking the target platform into account.
It is a subdirectory of @code{GNUSTEP_LIBRARIES_ROOT} and is where
libraries that do not depend upon the library combination, GNUstep or
others, should be placed.  This variable is dependent upon the
@code{GNUSTEP_INSTALLATION_DIR} variable, so the path will change
accordingly if the user specifies a different installation root
directory.
@end defvar

@defvar GNUSTEP_LIBRARIES
@code{GNUSTEP_LIBRARIES} is the absolute path for the directory where
libraries are installed taking the target platform and library
combination into account.  It is a subdirectory of
@code{GNUSTEP_TARGET_LIBRARIES} and therefore a subdirectory of
@code{GNUSTEP_LIBRARIES_ROOT}.  This directory is generally where
library project types, see @ref{library.make}, will install the library
file.  This variable is dependent upon the
@code{GNUSTEP_INSTALLATION_DIR} variable, so the path will change
accordingly if the user specifies a different installation root
directory.
@end defvar

@defvar GNUSTEP_RESOURCES
@code{GNUSTEP_RESOURCES} is the absolute path for the directory where
resource files are installed; example resources are fonts, printer type
information, model files for system panels, and system images.  The
resource files are generally associated with libraries, because
resources for applications or bundles are included within the
application or bundle directory wrapper.  @code{GNUSTEP_RESOURCES} is a
subdirectory of @code{GNUSTEP_LIBRARIES_ROOT}; it is dependent upon the
@code{GNUSTEP_INSTALLATION_DIR} variable, so the path will change
accordingly if the user specifies a different installation root
directory.
@end defvar

@defvar GNUSTEP_HOST_DIR
@code{GNUSTEP_HOST_DIR} is the subdirectory path for the host platform CPU
and operating system.  It is a composed from the @code{GNUSTEP_HOST_CPU}
and @code{GNUSTEP_HOST_OS} variables.
@end defvar

@defvar GNUSTEP_TARGET_DIR
@code{GNUSTEP_TARGET_DIR} is the subdirectory path for the target platform
CPU and operating system.  It is composed from the
@code{GNUSTEP_TARGET_CPU} and @code{GNUSTEP_TARGET_OS} variables.
@code{GNUSTEP_TARGET_DIR} is generally used as part of the installation
path when platform specific files are installed.
@end defvar

@defvar GNUSTEP_OBJ_DIR
@code{GNUSTEP_OBJ_DIR} is the subdirectory path where the Makefile
Package places binary files: object files, libraries, executables,
produced by the compiler.  The Makefile Package separates binary files
for different target platforms, different library combinations, and
different compile options into different directories; these different
directories are subdirectories from the current directory where the
makefile resides.  This structure allows a package to be compiled for
different target platforms, different library combinations, and
different compile options @emph{in place}; i.e. the binary files are
separated from each other so a compile pass from one set of options do
not overwrite or erase binary files from a previous compile pass with
different options.  Generally the user does not use this variable;
however, if the package needs to manually install some binary files than
the makefile fragment uses this variable to reference the path where the
binary file is located.
@end defvar

@node Scripts, Platform Information, Directory Paths, Common Variables
@subsection Scripts

@defvar CONFIG_GUESS_SCRIPT
@code{CONFIG_GUESS_SCRIPT} is the absolute path to the
@file{config.guess} script within the Makefile Package; this script is
used to determine host and target platform information.  The Makefile
Package executes this script to determine the values of the host
platform variables: @code{GNUSTEP_HOST}, @code{GNUSTEP_HOST_CPU},
@code{GNUSTEP_HOST_VENDOR}, @code{GNUSTEP_HOST_OS}, and the target
platform variables: @code{GNUSTEP_TARGET}, @code{GNUSTEP_TARGET_CPU},
@code{GNUSTEP_TARGET_VENDOR}, @code{GNUSTEP_TARGET_OS}; generally the
user does not need to execute this script because the Makefile Package
executes it automatically.
@end defvar

@defvar CONFIG_SUB_SCRIPT
@code{CONFIG_SUB_SCRIPT} is the absolute path to the @file{config.sub}
script within the Makefile Package; this script takes a platform name
and canonicalizes it, i.e. it puts the name in a standard form.  The
Makefile Package uses this script when the user specifies a target
platform for compilation; the target platform name is canonicalized so
that the Makefile Package can properly parse the name into its different
components.  Generally the user does not execute this script.
@end defvar

@defvar CONFIG_CPU_SCRIPT
@code{CONFIG_CPU_SCRIPT} is the absolute path to the @file{cpu.sh}
script within the Makefile Package; this script extracts the CPU name
from a canonicalized platform name.  Generally the user does not execute
this script; it is used internally by the Makefile Package.
@end defvar

@defvar CONFIG_VENDOR_SCRIPT
@code{CONFIG_VENDOR_SCRIPT} is the absolute path to the @file{vendor.sh}
script within the Makefile Package; this script extracts the vendor name
from a canonicalized platform name.  Generally the user does not execute
this script; it is used internally by the Makefile Package.
@end defvar

@defvar CONFIG_OS_SCRIPT
@code{CONFIG_OS_SCRIPT} is the absolute path to the @file{os.sh} script
within the Makefile Package; this script extracts the operating system
name from a canonicalized platform name.  Generally the user does not
execute this script; it is used internally by the Makefile Package.
@end defvar

@defvar CLEAN_CPU_SCRIPT
@code{CLEAN_CPU_SCRIPT} is the absolute path to the @file{clean_cpu.sh}
script within the Makefile Package; this script takes a platform CPU
name and @emph{cleans} it for use by the Makefile Package.  The process
of cleaning refers to the situation where numerous equivalent
processors, which have different names, are mapped to a single name.
For example, the Intel line of processors: i386, i486, Pentium, all have
different CPU names, but the Makefile Package considers them equivalent
and cleans those names so that the single name @file{ix86} is used.
Generally the user does not execute this script; it is used internally
by the Makefile Package.
@end defvar

@defvar CLEAN_VENDOR_SCRIPT
@code{CLEAN_VENDOR_SCRIPT} is the absolute path to the
@file{clean_vendor.sh} script within the Makefile Package; this script
takes a platform vendor name and @emph{cleans} it for use by the
Makefile Package.  The process of cleaning refers to the situation where
numerous equivalent vendors, which have different names, are mapped to a
single name.  Generally the user does not execute this script; it is
used internally by the Makefile Package.
@end defvar

@defvar CLEAN_OS_SCRIPT
@code{CLEAN_OS_SCRIPT} is the absolute path to the @file{clean_os.sh}
script within the Makefile Package; this script takes a platform
operating system name and @emph{cleans} it for use by the Makefile
Package.  The process of cleaning refers to the situation where numerous
equivalent operating systems, which have different names, are mapped to
a single name.  Generally the user does not execute this script; it is
used internally by the Makefile Package.
@end defvar

@node Platform Information, Library Combination, Scripts, Common Variables
@subsection Host and Target Platform Information

@defvar GNUSTEP_HOST
@code{GNUSTEP_HOST} is the canonical host platform name; i.e. the name
of the platform which is performing compilation of programs.  For
example, a SPARC machine by Sun Microsystems running the Solaris 2.5.1
operating system has the name @code{sparc-sun-solaris2.5.1}.
@end defvar

@defvar GNUSTEP_HOST_CPU
@code{GNUSTEP_HOST_CPU} is the CPU name for the canonical host platform
name; i.e. the name of the CPU platform which is performing compilation
of programs.  The Makefile Package cleans this CPU name with the
@code{CLEAN_CPU_SCRIPT} script before using it internally.  For example,
the canonical host platform name of @code{i586-pc-linux-gnu} has a CPU
name of @code{ix86}.
@end defvar

@defvar GNUSTEP_HOST_VENDOR
@code{GNUSTEP_HOST_VENDOR} is the vendor name for the canonical host
platform; i.e. the name of the vendor platform which is performing
compilation of programs.  The Makefile Package cleans this vendor name
with the @code{CLEAN_VENDOR_SCRIPT} script before using it internally.
For example, the canonical host platform name of
@code{sparc-sun-solaris2.5.1} has a vendor name of @code{sun}.
@end defvar

@defvar GNUSTEP_HOST_OS
@code{GNUSTEP_HOST_OS} is the operating system name for the canonical
host platform; i.e. the name of the operating system platform which is
performing compilation of programs.  The Makefile Package cleans this
operating system name with the @code{CLEAN_OS_SCRIPT} script before
using it internally.  For example, the canonical host platform name of
@code{i586-pc-linux-gnu} has an operating system name of
@code{linux-gnu}.
@end defvar

@defvar GNUSTEP_TARGET
@code{GNUSTEP_TARGET} is the canonical target platform name;
i.e. compilation of programs generate object code for this platform.  By
default the target platform is the same as the host platform unless the
user specifies a different target when running make, see Cross
Compiling.
@end defvar

@defvar GNUSTEP_TARGET_CPU
@code{GNUSTEP_TARGET_CPU} is the CPU name for the canonical target
platform; i.e. compilation of programs generate object code for this CPU
platform.  The Makefile Package cleans this operating system name with
the @code{CLEAN_CPU_SCRIPT} script before using it internally.  By
default the target CPU platform is the same as the host CPU platform,
@code{GNUSTEP_HOST_CPU}, unless the user specifies a different target
platform when running make, see Cross Compiling.
@end defvar

@defvar GNUSTEP_TARGET_VENDOR
@code{GNUSTEP_TARGET_VENDOR} is the vendor name for the canonical target
platform; i.e. compilation of programs generate object code for this
vendor platform.  The Makefile Package cleans this vendor name with the
@code{CLEAN_VENDOR_SCRIPT} script before using it internally.  By
default the target vendor platform is the same as the host vendor
platform, @code{GNUSTEP_HOST_VENDOR}, unless the user specifies a
different target platform when running make, see Cross Compiling.
@end defvar

@defvar GNUSTEP_TARGET_OS
@code{GNUSTEP_TARGET_OS} is the operating system name for the canonical
target platform; i.e. compilation of programs generate object code for
this operating system platform.  The Makefile Package cleans this
operating system name with the @code{CLEAN_OS_SCRIPT} script before
using it internally.  By default the target operating system platform is
the same as the host operating system platform, @code{GNUSTEP_HOST_OS},
unless the user specifies a different target platform, see Cross
Compiling.
@end defvar

@node Library Combination, Overridable Flags, Platform Information, Common Variables
@subsection Library Combination

@defvar OBJC_RUNTIME_LIB
@code{OBJC_RUNTIME_LIB} is assigned the code that indicates the
Objective-C Runtime library which compiled Objective-C programs will
use; the three possible values are: @samp{gnu} for the GNU Runtime,
@samp{nx} for the NeXT Runtime, and @samp{sun} for the Sun Microsystems
Runtime.  The Objective-C Runtime library can be changed to use a
library other than the default with the @samp{library_combo} make
parameter, see @ref{Running Make} for more details.  Read @ref{Library
Combination} for more information on how the Makefile Package handles
different library combinations.  If a makefile must perform specific
operations dependent upon the Objective-C Runtime library then this
variable is the one to check.
@end defvar

@defvar RUNTIME_DEFINE
@code{RUNTIME_DEFINE} is assigned a preprocessor flag that can be passed
to the compiler which defines a macro based upon the Objective-C Runtime
library that compiled Objective-C programs will use.  This macro is
useful if the compiled program must execute different code based upon
the Objective-C Runtime being used.  See @ref{GNUmakefile.preamble} for an
example on how to pass this preprocessor flag when compiling.  The three
possible values are: @samp{-DGNU_RUNTIME=1} for the GNU Runtime,
@samp{-DNeXT_RUNTIME=1} for the NeXT Runtime, and @samp{-DSun_RUNTIME=1}
for the Sun Microsystems Runtime.
@end defvar

@defvar FOUNDATION_LIB
@code{FOUNDATION_LIB} is assigned the code that indicates the Foundation
Kit library, as specified by the OpenStep specification, which compiled
Objective-C programs will use; the four possible values are: @samp{gnu}
for the GNUstep Base Library, @samp{nx} for the NeXT Foundation Kit
Library, @samp{sun} for the Sun Microsystems Foundation Kit Library, and
@samp{fd} for the libFoundation Library.  The Foundation Kit library can
be changed to use a library other than the default with the
@samp{library_combo} make parameter, see @ref{Running Make} for more details.
Read @ref{Library Combination} for more information on how the Makefile
Package handles different library combinations.  If a makefile must
perform specific operations dependent upon the Foundation Kit library
then this variable is the one to check.
@end defvar

@defvar FND_DEFINE
@code{FND_DEFINE} is assigned a preprocessor flag that can be passed to
the compiler which defines a macro based upon the Foundation Kit
library, as specified by the OpenStep specification, which compiled
Objective-C programs will use.  This macro is useful if the compiled
program must execute different code based upon the Foundation Kit
library being used.  See @ref{GNUmakefile.preamble} for an example on how to pass
this preprocessor flag when compiling.  The four possible values are:
@samp{-DGNUSTEP_BASE_LIBRARY=1} for the GNUstep Base Library,
@samp{-DNeXT_Foundation_LIBRARY=1} for the NeXT Foundation Kit Library,
@samp{-DSun_Foundation_LIBRARY=1} for the Sun Microsystems Foundation
Kit Library, and @samp{-DLIB_FOUNDATION_LIBRARY=1} for the libFoundation
Library.
@end defvar

@defvar GUI_LIB
@code{GUI_LIB} is assigned the code that indicates the Application Kit
library, as specified by the OpenStep specification, which compiled
Objective-C programs will use; the two possible values are: @samp{gnu}
for the GNUstep GUI Library and @samp{nx} for the NeXT Application Kit
Library.  The Application Kit library can be changed to use a library
other than the default with the @samp{library_combo} make parameter, see
@ref{Running Make} for more details.  Read @ref{Library Combination} for more
information on how the Makefile Package handles different library
combinations.  If a makefile must perform specific operations dependent
upon the Application Kit library then this variable is the one to check.
@end defvar

@defvar GUI_DEFINE
@code{GUI_DEFINE} is assigned a preprocessor flag that can be passed to
the compiler which defines a macro based upon the Application Kit
library, as specified by the OpenStep specification, which compiled
Objective-C programs will use.  This macro is useful if the compiled
program must execute different code based upon the Application Kit
library being used.  See @ref{GNUmakefile.preamble} for an example on how
to pass this preprocessor flag when compiling.  The two possible values
are: @samp{-DGNUSTEP_GUI_LIBRARY=1} for the GNUstep GUI Library and
@samp{-DNeXT_Application_LIBRARY=1} for the NeXT Application Kit
Library.
@end defvar

@defvar GUI_BACKEND_LIB
@code{GUI_BACKEND_LIB} is assigned the code that indicates the backend
library which compiled Objective-C programs will use in conjunction with
the GNUstep GUI Library.  The three possible values are: @samp{xdps} for
the GNUstep X/DPS GUI Backend Library, @samp{nsx} for the NSKit GUI
Backend Library, and @samp{w32} for the MediaBook WIN32 GUI Backend
Library.  @code{GUI_BACKEND_LIB} is only relevant when @code{GUI_LIB} is
set to @samp{gnu}; otherwise, @code{GUI_BACKEND_LIB} will be set to
@samp{nil} to indicate that there is no backend library.
@code{GUI_BACKEND_LIB} can be changed to use a library other than the
default with the @samp{library_combo} make parameter, see @ref{Running
Make} for more details.  Read @ref{Library Combination} for more
information on how the Makefile Package handles different library
combinations.  If a makefile must perform specific operations dependent
upon the backend library then this variable is the one to check.
@end defvar

@defvar GUI_BACKEND_DEFINE
@code{GUI_BACKEND_DEFINE} is assigned a preprocessor flag that can be
passed to the compiler which defines a macro based upon the backend
library which compiled Objective-C programs will use in conjunction with
the GNUstep GUI Library.  This macro is useful if the compiled program
must execute different code based upon the backend library being used.
See @ref{GNUmakefile.preamble} for an example on how to pass this
preprocessor flag when compiling.  The three possible values are:
@samp{-DXDPS_BACKEND_LIBRARY=1} for the GNUstep X/DPS GUI Backend
Library, @samp{-DNSX_BACKEND_LIBRARY=1} for the NSKit GUI Backend
Library, and @samp{-DW32_BACKEND_LIBRARY=1} for the MediaBook WIN32 GUI
Backend Library.  @code{GUI_BACKEND_DEFINE} is not defined if there is
not backend library; i.e. @code{GUI_BACKEND_LIB} is @samp{nil}.
@end defvar

@node Overridable Flags,  , Library Combination, Common Variables
@subsection Overridable Flags

@defvar OBJCFLAGS
@code{OBJCFLAGS} are flags that are passed to the compiler when
compiling Objective-C files.  The user can override this variable when
running make and specify different flags as the following command
illustrates:
@end defvar

@smallexample
make OBJCFLAGS="-Wno-implicit -Wno-protocol"
@end smallexample

@defvar CFLAGS
@code{CFLAGS} are flags that are passed to the compiler when compiling C
files.  The user can override this variable when running make and
specify different flags as the following command illustrates:
@end defvar

@smallexample
make CFLAGS="-Wall"
@end smallexample

@defvar OPTFLAG
@code{OPTFLAG} is the flag used to indicate the optimization level that
the compiler should perform when compiling Objective-C and C files; this
flag is set to @samp{-O2} by default, but the user can override this
setting when running make as the following command illustrates:
@end defvar

@smallexample
make OPTFLAG=
@end smallexample

This command sets the optimization flag to be empty so that no
optimization will be performed by the compiler.

@defvar GNUSTEP_INSTALLATION_DIR
@code{GNUSTEP_INSTALLATION_DIR} is the root directory where the package
will install its files; overriding this variable when running make will
change all of the variables within the Makefile Package that depend upon
it; the following command illustrates the use of this variable:
@end defvar

@smallexample
make GNUSTEP_INSTALLATION_DIR="/GNUstep"
@end smallexample

This command states that the @file{/GNUstep} directory should be used as
the installation root directory; applications in the package will be
installed under @file{/GNUstep/Apps} directory, libraries in the package
will be installed under the @file{/GNUstep/Library/Libraries} directory,
command line tools will be installed under the @file{/GNUstep/Tools}
directory, and etc.  By default the Makefile Package sets
@code{GNUSTEP_INSTALLATION_DIR} to @code{GNUSTEP_LOCAL_ROOT} unless
@code{GNUSTEP_LOCAL_ROOT} is empty in which case
@code{GNUSTEP_INSTALLATION_DIR} will be set to
@code{GNUSTEP_SYSTEM_ROOT}.  Some packages will also override
@code{GNUSTEP_INSTALLATION_DIR} within their makefile to force the
package to install in (say) @code{GNUSTEP_SYSTEM_ROOT} instead of the
default @code{GNUSTEP_LOCAL_ROOT} directory, but if the user sets the
value of @code{GNUSTEP_INSTALLATION_DIR} when running make then that
setting takes precedence over all others.

@bye