Hans-Peter Nilsson wrote: > > From: Ulrich Weigand <uweig...@de.ibm.com> > > Date: Tue, 25 Aug 2015 14:59:05 +0200 > > > The other GCC run-time libraries rely on libtool to figure out > > that even though -fPIC works, dynamic libraries are still not > > supported on the platform, and thus compile everything for > > static linking (i.e. without -fPIC). > > That's not what I see, at least not the "figuring out" part. > (They mostly use libtool as-is; some test tuples, but some test > version-script support and add it then.)
Well, the "figuring out" is implicit; because libtool knows the platform does not support dynamic linking, it defaults to --disable-shared, which means only static libraries are being built; and the default compile option when building static libraries does not use -fPIC. > I'll leave that to you to sort out, but if you chose to use > $can_build_shared, consider also setting PIC_FLAG to $pic_flag > (instead of plain -fPIC). In the meantime I'll commit my patch > as it solves *some* of the breakage; for targets erroring on -fPIC. > > ...but reading the libtool documention I think I found a much > better solution: Let's just add -prefer-pic when compiling > libbacktrace. It leaves everything to libtool. Can you please > test this? Hmm, reading the documentation an even simpler version that has equivalent effect to yours should be just adding the pic-only option when calling LT_INIT. However, neither works for the SPU, because in both cases libtool will only do the test whether the target supports the -fPIC option. It will not test whether the target supports dynamic libraries. [ It will do that test; and default to --disable-shared on SPU. That is a no-op for libbacktrace however, since it calls LT_INIT with the disable-shared option anyway. When adding back the -fPIC flag due to either the pic-only LT_INIT option or the -prefer-pic libtool command line option, it does not check for that again. ] Bye, Ulrich -- Dr. Ulrich Weigand GNU/Linux compilers and toolchain ulrich.weig...@de.ibm.com
