Block objects [1] are a C-level syntactic and runtime feature. They
are similar to standard C functions, but in addition to executable
code they may also contain variable bindings to automatic (stack)
or managed (heap) memory. A block can therefore maintain a set of
state (data) that it can use to impact behavior when executed.
This port is based on Apple's GCC 5646 with some bugfixes from
Apple GCC 5666.3. It has some small differences with the support
in clang, which remains the recommended compiler.
Perhaps the most notable difference is that in GCC that __block
is not actually a keyword, but a macro. There will be workaround
for this issue in a near future. Other issues can be consulted in
the clang documentation [2]
For better compatiblity with Apple's GCC and llvm-gcc some related
fixes and features from Apple have been included. Support for the
non-standard nested functions in GCC is now off by default.
No effort was made to update the ObjC support since FreeBSD doesn't
carry ObjC in the base system, but some of the code crept in and
was more difficult to remove than to adjust.
Reference:
[1]
https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/Blocks/Articles/00_Introduction.html
[2]
http://clang.llvm.org/compatibility.html#block-variable-initialization
Obtained from: Apple GCC 4.2
MFC after: 3 weeks
Google released and enhanced version of gcc-4.2.1 plus their local
patches for Android[1].
The patches are owned by Google and the license hasn't been changed
from the original GPLv2. We are only bringing a subset of the
available patches that may be helpful in FreeBSD. Changes specific
to android are not included.
From the README.google file[1].
Patches applied to google_vendor_src_branch/gcc/gcc-4.2.1:
gcc/Makefile.in
gcc/c-common.c
gcc/c-common.h
gcc/c-opts.c
gcc/c-typeck.c
gcc/cp/typeck.c
gcc/doc/invoke.texi
gcc/flags.h
gcc/opts.c
gcc/tree-flow.h
gcc/tree-ssa-alias-warnings.c
gcc/tree-ssa-alias.c
Backport of -Wstrict-aliasing from mainline.
Silvius Rus <rus@google.com>
gcc/coverage.c:
Patch coverage_checksum_string for PR 25351.
Seongbae Park <spark@google.com>
Not yet submitted to FSF.
gcc/c-opts.c
gcc/c-ppoutput.c
gcc/c.opt
gcc/doc/cppopts.texi
libcpp/Makefile.in
libcpp/directives-only.c
libcpp/directives.c
libcpp/files.c
libcpp/include/cpplib.h
libcpp/init.c
libcpp/internal.h
libcpp/macro.c
Support for -fdirectives-only.
Ollie Wild <aaw@google.com>.
Submitted to FSF but not yet approved.
libstdc++-v3/include/ext/hashtable.h
http://b/742065http://b/629994
Reduce min size of hashtable for hash_map, hash_set from 53 to 5
libstdc++-v3/include/ext/hashtable.h
http://b/629994
Do not iterate over buckets if hashtable is empty.
gcc/common.opt
gcc/doc/invoke.texi
gcc/flags.h
gcc/gimplify.c
gcc/opts.c
Add Saito's patch for -finstrument-functions-exclude-* options.
gcc/common.opt
gcc/doc/invoke.texi
gcc/final.c
gcc/flags.h
gcc/opts.c
gcc/testsuite/gcc.dg/Wframe-larger-than.c
Add a new flag -Wframe-larger-than- which enables a new warning
when a frame size of a function is larger than specified.
This patch hasn't been integrated into gcc mainline yet.
gcc/tree-vrp.c
Add a hack to avoid using ivopts information for pointers starting
at constant values.
Reference:
[1]
https://android.googlesource.com/toolchain/gcc/+/master/gcc-4.2.1/
Obtained from: Google Inc.
MFC after: 3 weeks
1.2 framework for our kernel printf enhancements.
1.3 suppress prototype warnings on K&R main.
Both flag variables declared here were disconnected through the 5-current
lifetime and are retained here for backwards compatibility reasons only.