On Sun, Jul 17, 2016 at 10:04:13PM -0400, Patrick Palka wrote: > I did some digging to figure out the origin of libbackend.a. It was was > created to work around a command line length limit on a VAX system > (https://gcc.gnu.org/ml/gcc-bugs/2000-06/msg00438.html). The 1600 byte > command line that links cc1plus was too large for this system, so > libbackend.a was introduced and used in place of $(OBJS) to reduce the > size of this command line.
As Zack said in that thread, at the top of the mail you refer to here: "Putting the back end in a library seems like a good idea to me, never mind whether or not we're really hitting command line length limits." Many people agree with that. Some, anyway. > I suppose rebuild times could instead be further reduced by splitting > libbackend.a into multiple logical archives. It would also be a small > step towards making GCC more modular. Is it faster to not have one big archive? There are nine compilers. If you want to add -s to the ar flags (it is POSIX, most systems should have it by now), you should add a configure check (or find one, there is bound to be one somewhere already) to test for it, and then add it to AR_FLAGS (and there is also AR_CREATE_FOR_TARGET, it may be useful to add it there as well -- needs a separate test of course). Or, if using GNU ar, you can even use -S, if that helps (after testing for it in configure, of course). Segher
