Allow a thread to be GCed when it is blocked on a place
channel for reading and the place channel's write end
is inaccessible.
GC is limited to threads that do not participate in cycles
of such threads, where the otherwise unerachable threads
are blocked on place channels that are reachable among the
set of threads. In other words, the GC finds the greatest
fix point (as measured by the threads to retain) instead of
least fix point --- which isn't what you want, but finding
the least fix point seems to require significant extra GC
machinery across places.
This improvement was intended to solve the same problem as
commit 7b0608c, but that case seems to run into the limitation
on cycles.
A tail call with certain kinds of primitives would fail to
clear local bindings in a detectable way. For example, a
tail call to `sync' that blocks could retain references
to unreachable data in the context of the `sync' call.
Primitives that can cause problems in the run-time system
are already identified as "imemdiate" primitives. The
safe-for-space pass now inserts clearing actions before a tail
call, unless the call it to a known immediate primitive or a
Racket-implemented function.
Clearing operations are now omitted before non-tail calls
to immediate operations like structure predicates.
The newly added clearing operations could affect performance,
but they probably won't, since the clear operations are still
avoided in tail-call cases that are otherwise fast. The newly
omitted clearing operations may improve performance.
The shortcut could be triggered in a bad case (first
argument as `#f' in non-timeout mode) and returned the
wrong result (void instead of the semaphore).
Enable extflonums in a MSVC build by relying on a MinGW-built DLL,
"longdouble.dll". The DLL is loaded on startup. If the DLL isn't
available, then `extflonum-available?' reports #f.
Instead of setting the floating-point mode globally to extended
precision, the mode is changed only just before (and restored right
after) extflonum arithmetic operations.
Using an impersonator property to represent an application mark was
a bad choice. The property gets propagated, so it is also on any later
chaperone layer, and then things go bad: the docs say that special
treatment is triggered by supplying an argument to `impersonate-property',
but it was actually triggered by the chaperone having the property.
Change the implementation to match the documentation. Using an
impersonator property to supply the mark should be regarded as a hack,
but now the implementaiton is at least consistent with the documentaiton.
"-rdynamic" doesn't work with GCC 4.7 on OpenBSD: "cc: error:
unrecognized command line option '-rdynamic'". The switch isn't
necessary because it is only a wrapper to "-Wl,--export-dynamic".
Look GCC bug 37454.
For immutable hashes, `hash-iterate-{key,value}' used to take O(N) time on
the first call for a particular table and O(1) thereafter. Now it takes
O(1) time for all calls, the constant is only slightly larger for
the non-first calls, and there's no extra allocation.
The intent is to support phase-crossing data such as the `exn:fail:syntax'
structure type that is instantiaed by macros and recognized by contexts
that use `eval' or `expand'. Phaseless modules are highly constrained,
however, to avoid new cross-phase channels, and a module is inferred to
be phaseless when it fits syntactic constraints.
I've adjusted `racket/kernel' and improved its documentation a little
so that it can be used to implement a phaseless module (which can
import only from other phaseless modules).
This change also adds a `flags' field to the `mod' structure type
from `compiler/zo-structs'.
The bug was introduced when changing the order of unboxed argument
staging along with extflonum unboxing support. The main symptom of
the bug was that icons were sometimes blacked out in DrRacket.
The check was incomplete in the case that both arguments to a binary
[ext]flonum function need to be checked and the second one was not an
[ext]flonum and also not a fixnum.
The problem was exposed by improved error checking
in the expander to detect references to exports of a module that
is not yet visited, and as triggered by the documentation for
`2htdp/planetcute'.
Includes a repair for floating-point `min' and `max' that affects all
x86 builds that use SSE arithmetic, leaving the (otherwise unused)
floating-point stack in a bad state, which might have affected
x87-using C/foreign libraries running alongside Racket.
