On Sun, Nov 2, 2014 at 3:38 PM, Ned Deily <n...@acm.org> wrote: > In article > <cahu5pryq3xegtd-7ahzmdbwk32nprfxz24dfdm1oj-wnmyj...@mail.gmail.com>, > Cyd Haselton <chasel...@gmail.com> wrote: >> Just checking: is sincos() the same as sin() and cos()? Nm output for >> my toolchain's libm does show sin() and cos() just not sincos() > > See, this is what you get when you ask for free help: bad info.
Silly me...what was I thinking? > sincos > isn't the same, as a little of googling informs me. But, as the thread > starting here indicates: > I did a fairly exhaustive search for the sincos() error code I was getting and that link did not turn up for me at all. Instead I found a reference that seemed to imply that such a macro should be implemented but it was not implemented in GCC-4.8.0. Then again, the link you found doesn't seem to indicate which version of GCC has this feature...maybe it is versions later than 4.8.0... > https://sourceware.org/ml/binutils/2010-04/msg00219.html > > gcc can do an optimization that turns a pair of sin() and cos() calls > with the same arguments into a single call to sincos(). And there is > such a pair in Python's complexobject.c. As the thread explains, there > are some platforms where sin() and cos() are implemented but not > sincos(). As suggested in the thread, one approach is to give options > to gcc to avoid the optimizations: > > CFLAGS='-fno-builtin-sin -fno-builtin-cos' > > That does seem to result in a libpython with no references to sincos. Sounds good...I'll try it if bootstrapping 4.9.0 goes south. > > -- > Ned Deily, > n...@acm.org > > -- > https://mail.python.org/mailman/listinfo/python-list -- https://mail.python.org/mailman/listinfo/python-list
