ardour

History

Mads Kiilerich d220f477ed wscript: drop unused "mandatory variables" 'top' and 'out' in libs Variables by these names are only used from the local wscript and when running "waf configure", which already for other reasons only can run at the top-level. These variables are thus not mandatory and not used.		2023-09-17 07:34:55 -06:00
..
Makefile	if we can't determine the gcc4/5 prefer the new gcc5 ABI	2016-08-02 15:51:54 +02:00
README	new tool to test gcc4/5 ABI	2015-09-26 19:03:22 +02:00
abicheck.c	fix path to glibmm that we check	2016-08-12 13:46:17 +02:00
wscript	wscript: drop unused "mandatory variables" 'top' and 'out' in libs	2023-09-17 07:34:55 -06:00

README

g++5 ABI test tool
==================

This is a simple tool to test a system for g++5's glibmm at runtime.

GCC5.1 introduced a new ABI for the C++ standard library.
The old 3.4 .. 5.0 ABI is not compatible. By default gcc provides a
dual ABI, so testing libstc++ itself is not sufficient.


Some GNU/Linux distributions systems switched to the new ABI already
and compile *plugins* with the new gcc.

If a plugin uses a c++ library that is also shipped with ardour-bundles,
the ABI of that library must match. Currently known cases: gtkmm, glibmm.

e.g. Ingen or eq10q provided by a distro compiled with gcc5 will not
load in Ardour from ardour.org compiled with gcc4 because ardour
ships an incompatible gtkmm, glibmm, cairomm, ...

Likewise Ardour gcc5-compiled binaries will fail to load plugins that
are compiled with gcc4.

This simiple tool `gcc-glibmm-abi-check` checks for gcc4/gcc5 specific
symbols in libglibmm (a common denominator C++ lib), it is intended
to be run when deploying ardour binaries.


References
----------

https://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dual_abi.html
https://wiki.debian.org/GCC5
https://mail.gnome.org/archives/gtkmm-list/2015-June/thread.html