Re: help cross compiling again

[Tor Lillqvist <tml iki fi>]

(This list is for discussion about development of GTK+ itself. Your
message is more for gtk-app-devel-list.)

Marcelo Armengot writes:
 > -Ic:/devel/target/gtk+-2.10.7/include/gtk-2.0 
 > -Ic:/devel/target/gtk+-2.10.7/lib/gtk-2.0/include 
 > -Ic:/devel/target/atk-1.12.3/include/atk-1.0 
 > -Ic:/devel/target/cairo-1.2.6/include/cairo 

(etc)

This indicates that you are using .pc files that are intended for use
with a Windows build of pkg-config.

If you use them for cross-compilation, you need to edit the prefix
variable in the .pc files from the GTK+, atk, cairo, Pango and GLib
developer packages to correspond to the actual location where you
unpacked ("installed") them.

As distributed, the .pc files from the Win32 developer packages on
ftp.gtk.org and ftp.gnome.org have prefix variables pointing to
directories that do not exist on your (or any other)
machine. (Typically c:/devel/target/<package-name>.) This is as
intended, and *not* a bug. Read on.

If you think it *is* a bug, what would you then suggest should be the
value of prefix in the distributed .pc files? How could I know in
advance where you are going to unpack the developer package? This is
especially true on Windows, where one definitely never should assume
that *any* path exists on the end-user machines. Not all machines even
have a C: drive.

Everything I build and distribute for Windows is supposed to be freely
unpackable in any random location. My run-time packages (libraries,
executables) are even supposed to be installable in directories with
any random Unicode characters in their pathnames, even spaces and
characters not in the system codepage, like Greek on an English
Windows installation. If this doesn't work, *that* is a
bug. (pkg-config unfortunately doesn't work with spaces in path
names. This is a cross-platform feature of it.)

When running on Windows, pkg-config automatically knows to determine
the actual installation location of a package from where the .pc file
was found.

For instance, if somebody unpacks the Win32 GTK+ developer package
under the folder Z:\foo\dev, the gtk+-win32-2.0.pc file will be
Z:\foo\dev\lib\pkgconfig\gtk+-win32-2.0.pc. pkg-config will disregard
the prefix assignment in the .pc file and instead use Z:\foo\dev as
prefix for that .pc file.

On Unix, pkg-config doesn't do this. So you will have to edit the .pc
files.

Alternatively, maybe pkg-config should do that prefix override magic
on Unix, too? If you think so, please file a bug against it.

Or, somebody could take the Win32 developer packages and repackage
them into packages for their favourite Linux distro that would install
in a fixed location, with the .pc files already correct.

--tml