This cleans up a warning when building libm at higher WARNS levels and
makes the intent more clear. By the C standard the values are assigned
to subobject members in order so this change introduces no functional
change. (6.7.9 20)
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D8333
The C11 standard introduced a set of macros (CMPLX, CMPLXF, CMPLXL) that
can be used to construct complex numbers from a pair of real and
imaginary numbers. Unfortunately, they require some compiler support,
which is why we only define them for Clang and GCC>=4.7.
The cpack() function in libm performs the same task as CMPLX(), but
cannot be used to generate compile-time constants. This means that all
invocations of cpack() can safely be replaced by C11's CMPLX(). To keep
the code building with GCC 4.2, provide copies of CMPLX() that can at
least be used to generate run-time complex numbers.
This makes it easier to build some of the functions outside of libm.
* ld128/k_expl.h:
. Split out a computational kernel,__k_expl(x, &hi, &lo, &k) from expl(x).
x must be finite and not tiny or huge. The kernel returns hi and lo
values for extra precision and an exponent k for a 2**k scale factor.
. Define additional kernels k_hexpl() and hexpl() that include a 1/2
scaling and are used by the hyperbolic functions.
* ld80/s_expl.c:
* ld128/s_expl.c:
. Use the __k_expl() kernel.
Obtained from: bde
