#1154 Support out-of-source build in GTK makefiles

[Colomban Wendling]

It is nice to be able to build GTK2 and GTK3 versions of Scintilla and SciTE easily and separately.

Attached patches add support for building both Scintilla and SciTE outside the gtk/ directory. A caller will do something like make -f /path/too/gtk/makefile srcdir=/path/too/gtk, and all built files (but the resulting scintilla.a and SciTE) are placed in the current (build) directory.

For example, I myself created a directory gtk/_build_gtk3 and create a small custom makefile calling the normal one (for my settings and convenience):

#!/usr/bin/make -f

export srcdir=..
export prefix=$(shell pwd)/_install
export GTK3=1

all clean install uninstall analyze deps:
    $(MAKE) -f $(srcdir)/makefile $@

And I have the same (minus GTK3=1) in gtk/_build_gtk2, so all I have to do is make -C gtk/_build_gtk[23] and have the version I want, not conflicting with the other.

The only problem that remains is that scintilla.a and the SciTE binary are generated in the same place as before, i.e. somewhere in the source directory (under bin/). For Scintilla it makes some sense as SciTE's makefile search it there, but maybe there could be a way to override this?
Anyway, it "simply" requires to re-link scintilla.a with the appropriate GTK build before linking SciTE. Not perfect, but not so bad.

[Neil Hodgson]

Committed as [1bc6c3] and [5a1757] with feature# included in commit message.