Other major changes:
- pg code now uses only binary format
- pg timestamptz now always UTC (tz = 0), added doc section
- added contracts to most pg "can't-convert" errors
choose to print to pdf as well. Also, enable the preference
under linux (ie, make it available to be chosen-- all platforms
still default to printing via the platform-specific mechanism)
Support for break clauses complicates expansion to `for/fold/derived';
a new `syntax/for-body' library provides a helper for macros that need
to split a `for'-style body into a prefix part and wrappable part.
Allows the use of `in-generator' to produce multiple values in a
position other than immediately within `for' (where the arity
can be inferred).
Closes PR 11662
A recent bug fix involved moving part of an `editor-canvas%' resize
out of atomic mode by queueing a callback (because the resize involves
quesrying the editor for its size, etc.), but then the callback
happens after a canvas is shown, which can cause it to appear with
bogus initial scrollbars. Queue the callback instead as a "refresh"
level callback, which gets a chance to run before a frame is made
visible.
JIT-generated doesn't actually conform to the constraints
of the Win64 stack-unwind protocol. In pariticular,
JITted code might move the stack pointer after a "preamble"
that saves non-volatiles, and the frame pointer isn't in
the right place. So, we can't implement the generic unwind
hook --- but the JIT's stack traversal can interleave its own
unwinding with the OS-supplied unwinding interface.
The new parameter (and supporting environment variables and
command-line flags) can bytecode lookup to a tree other than
where a source file resides, so that sources and generated
compiled files can be kept separate. It also supports storing
bytecode files in a version-specific location (either with
the source or elsewhere).
