On 21 October 2018 at 16:01, Peter Maydell <peter.mayd...@linaro.org> wrote: > Any idea what's going on here? tcg/tcg.h has a comment saying > * The cmpxchg functions are only defined if HAVE_CMPXCHG128 > so presumably the issue is that the helper-a64 code is > trying to refer to them anyway. There certainly doesn't > seem to be any kind of #defining around the listed functions > in helper-a64.c to stop them being compiled in this situation. > > NB: I build with --enable-debug in this tree -- are you > perhaps accidentally relying on the compiler's optimisation > to discard these functions if they're not needed?
Adding a #if HAVE_CMPXCHG128 around the helper-a64.c functions just pushes the link error back a step to the references to those helpers: LINK aarch64-softmmu/qemu-system-aarch64w.exe tcg/tcg.o:tcg.c:(.rdata+0x9810): undefined reference to `helper_paired_cmpxchg64_le_parallel' tcg/tcg.o:tcg.c:(.rdata+0x9830): undefined reference to `helper_paired_cmpxchg64_be_parallel' tcg/tcg.o:tcg.c:(.rdata+0x9840): undefined reference to `helper_casp_le_parallel' tcg/tcg.o:tcg.c:(.rdata+0x9850): undefined reference to `helper_casp_be_parallel' which in turn I guess is because they're in the array of all helpers in tcg.c, so we need to also #if out the prototypes in helper-a64.h, which is awkward because there we don't have the HAVE_CMPXCHG128 defined... thanks -- PMM
