* Preliminary documentation about Multi-Thread, Async-Signal and
Async-Cancel Safety has been added.
+
+* Change of ABI data structures for s390 and s390x:
+ On s390 and s390x the size of struct ucontext and jmp_buf was increased to
+ allow for future hardware extensions. All library functions that accept or
+ return these structures were versioned in order to provide backwards
+ compatibility with existing code. However, not all cases can be handled
+ with interface versioning. If an application embeds either structure into
+ another structure and that structure is passed to another compilation unit
+ which expects the newer larger-sized object then any access to the new
+ fields will result in undefined behaviour. Similarly any access to fields
+ that were moved by the enlarging of the structures will cause undefined
+ behaviour. To fix the undefined behaviour all objects that are part of the
+ final in-memory image must agree on the size of structures, and this may
+ require recompilation.
\f
Version 2.18