http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50880
Bug #: 50880
Summary: __complex_acosh() picks wrong complex branch
Classification: Unclassified
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: krec...@ginac.de
According to the C++ standard, acosh(complex<T>) should behave just like C99's
cacosh(T complex) function. There, the branch cut is "at values less than 1
along the real axis" and the "range of a half-strip of non-negative values
along the real axis and in the interval [-i*pi,+i*pi] along the imaginary
axis."
The implementation in tr1/complex gets this wrong. The result returned by
__complex_acosh() are all wrong in the lower complex plain. It can be easily
fixed. I'm attaching a patch.
