tuck@jason.cs.unc.edu (Russ Tuck) (09/30/89)
In article <6602@thor.acc.stolaf.edu> mike@thor.stolaf.edu () writes: > >1. You can use g++ for commercial work. > >2. You cannot use libg++ in commercial products without bringing > them within the scope of the GNU license. We may change this in > the future, if we think that is the only way GNU will be accepted > into widespread use. But we will look long and hard at such a > change first. Until g++ 1.36 changed the way it links programs, this made sense to me. In effect, it says there's no copyleft on your executable unless you explicitly link in something copylefted (like libg++.a). However, g++ 1.36 now requires "-lg++" to link ANY program. So the above rules now make it impossible to use g++ without making the executable copylefted. (g++ compiles "main()" to include a call to "___main()", which is contained in libg++.a.) I consider this a bug in g++, or a dramatic policy change. (This isn't an immediate issue for me, since I'm currently at a Univ. and don't charge money when I share my code anyway. But I'm still surprised at the change.) Russ Tuck tuck@cs.unc.edu UNC Dept. of Computer Science ...!mcnc!unc!tuck CB# 3175 Sitterson Hall Chapel Hill, NC 27599-3175, USA (919) 962-1755 or 962-1932
schmidt@zola.ics.uci.edu (Doug Schmidt) (09/30/89)
In article <9741@thorin.cs.unc.edu>, tuck@jason (Russ Tuck) writes: >Until g++ 1.36 changed the way it links programs, this made sense to me. >In effect, it says there's no copyleft on your executable unless you >explicitly link in something copylefted (like libg++.a). > >However, g++ 1.36 now requires "-lg++" to link ANY program. So the above >rules now make it impossible to use g++ without making the executable >copylefted. (g++ compiles "main()" to include a call to "___main()", >which is contained in libg++.a.) > >I consider this a bug in g++, or a dramatic policy change. It is a policy change, but not in the direction you imply above. You are referring, of course, to the gnulib3.c file with the beta release of g++ 1.36. Please look at the file right now (I assume you've got access to it, or you wouldn't be writing this ;-)). Note how this file differs from most of the other libg++ files. In fact, it looks much like the gnulib.c and gnulib2.c from the gcc release, in that it doesn't contain a copyright notice at the top. This omission means that linking with the small `compiler-helper' functions declared in this file does *not* by itself bring the executable under the copyleft (the same may not hold for other libg++ files...). In fact, certain changes to g++ 1.36 (e.g., omitting the need for a special crt0.o file) specifically mean that you *can* use the g++ compiler (and its small helper functions in the gnulib[23]?.c files) without necessarily bringing the entire program under the copyleft (assuming, of course, that you don't include the copylefted libraries from libg++, etc.). The situation described in the previous paragraph was not true with previous releases g++. That is why I said above that there was a policy change, but not in the direction you implied! I know at this point that Jim Adcock will step in and say that this whole g++/libg++ library situation is unduly confusing. I agree with him. I hope that my explanation has helped shed a little light on an often easily mis-understood issue. Doug -- schmidt@ics.uci.edu (ARPA) | Per me si va nella citta' dolente. office: (714) 856-4043 | Per me si va nell'eterno dolore. | Per me si va tra la perduta gente. | Lasciate ogni speranza o voi ch'entrate.
tiemann@LURCH.STANFORD.EDU (Michael Tiemann) (10/02/89)
However, g++ 1.36 now requires "-lg++" to link ANY program. So the above
rules now make it impossible to use g++ without making the executable
copylefted. (g++ compiles "main()" to include a call to "___main()",
which is contained in libg++.a.)
I consider this a bug in g++, or a dramatic policy change.
Why don't you look at where __main really comes from, and check the
copyleft on that file. You will not find one. It is just a matter of
convenience that it comes from libg++.a. If you want to jump through
the various hoops to get it from elsewhere, that is your configuration
business.
Michael