The wrapper implementations of ldexp / scalbn / scalbln
(architecture-independent), and their float / long double variants,
return sNaN for sNaN input. This patch fixes them to add relevant
arguments to themselves so that qNaN is returned in this case.
Tested for x86_64 and x86.
[BZ #20225]
* math/s_ldexp.c (__ldexp): Add non-finite or zero argument to
itself.
* math/s_ldexpf.c (__ldexpf): Likewise.
* math/s_ldexpl.c (__ldexpl): Likewise.
* math/w_scalbln.c (__w_scalbln): Likewise.
* math/w_scalblnf.c (__w_scalblnf): Likewise.
* math/w_scalblnl.c (__w_scalblnl): Likewise.
* math/libm-test.inc (scalbn_test_data): Add sNaN tests.
(scalbln_test_data): Likewise.
Errno is not set and the testcases will fail.
Now the scalbln-aliases are removed in i386/m68
and the wrappers are used when calling the scalbln-functions.
On ia64 only scalblnf has its own implementation.
For scalbln and scalblnl the ieee754/dbl-64 and ieee754/ldbl-96 are used, thus
the wrappers are needed, too.
