This file records noteworthy changes.
+1.7.1 (2 October 2016)
+* Fix crash in basic::subs(), visible in classes which don't override it.
+* Fix convergence failure in Li_projection.
+* Fix cliffor_bar() and clifford_star().
+* Improve performance of clifford_to_lst().
+* Fix compilation issues, reduce compiler warnings.
+
+1.7.0 (30 April 2016)
+* Make use of C++11 features:
+ - Use new language features 'auto', 'nullptr', 'constexpr', range-based for
+ loops, the contextual keyword 'override', static 'noexcept' operator, etc.
+ - Add initializer list ctors for container<>, lst and nested initializer
+ lists ctor for class matrix.
+ - Add many rvalue reference overloads for ctors from std containers. (Note
+ that whether they really speed up things depends on whether evaluation
+ leaves the container unchanged or not.)
+ - Rvalue reference overloads for ctors from std containers made it possible
+ to remove the manual 'discardable' hack and std::auto_ptr<T> for good.
+ - New dynallocate<T>(args...) helper functions obsolete manual allocation
+ on the heap and setting the dynallocated status flag.
+ - Got rid of C++98ish algorithm features (bind2nd, etc.) and replaced them
+ with lambdas.
+* Make add::eval(), mul::eval() more careful so they return an evaluated,
+ canonical expression without compromise.
+* Remove 'level' argument of all .eval() methods. This has become possible by
+ ensuring that add::eval() and mul::eval() evaluate their own structure
+ without compromise (this was not guaranteed before). If all ex are evaluated,
+ any object which is an aggregate of such ex will only ever have to
+ evaluate itself, obsoleting the need for recursing.
+* Remove 'level' arguments of all .evalf() and .normal() methods. They were
+ modeled after the .eval() methods.
+* Make relational::rhs() and lhs() nonvirtual.
+* Add support for power::info(info_flags::real).
+* Add fderivative::derivatives() method.
+* Remove broken info_flags::algebraic.
+* Remove unmaintained support for Cint.
+* Remove unfinished andcode for hash table-based expairseq.
+* Remove deprecated ex::to_rational(lst) and ex::to_polynomial(lst).
+* ginac-excompiler installs in $LIBEXECDIR now, not in $BINDIR.
+* Many minor performance enhancements.
+
+1.6.7 (29 February 2016)
+* Fix elusive bug in sqrfree(), normal(), numer(), and denom().
+
1.6.6 (20 December 2015)
* Fix elusive bug in add::eval().
* Several minor performance enhancements.