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分享大家注意了~，checked_iterator影响performance
在VC2005以上环境下，用M$的STL库时，涉及到容器和迭代器的代码，如果特别在意Performance，需要使用_SECURE_SCL开关，避免内置的checked_iterator所带来的影响~
因为M$并没有在release模式下关闭此_SECURE_SCL开关，具体信息可以看：
http://msdn.microsoft.com/en-us/library/aa985965(VS.80).aspx
http://askldjd.wordpress.com/tag/checked-iterator/
http://channel9.msdn.com/shows/Going+Deep/STL-Iterator-Debugging-and-Secure-SCL/
如果希望再release模式下避免无谓的牺牲，具体做法就是在包含STL任意头文件之前使用
C++一直提倡：不要为不必要的东西而买单！
纯属散分，欢迎讨论~
因为M$并没有在release模式下关闭此_SECURE_SCL开关，具体信息可以看：
http://msdn.microsoft.com/en-us/library/aa985965(VS.80).aspx
http://askldjd.wordpress.com/tag/checked-iterator/
http://channel9.msdn.com/shows/Going+Deep/STL-Iterator-Debugging-and-Secure-SCL/
如果希望再release模式下避免无谓的牺牲，具体做法就是在包含STL任意头文件之前使用
#ifndef _DEBUG
#define _SECURE_SCL 0
#endif
C++一直提倡：不要为不必要的东西而买单！
纯属散分，欢迎讨论~
...全文
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yowang_ 2010-07-20
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前来学习！
nbabest23 2010-07-20
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学习！
wang23432 2010-07-20
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学习了，谢谢
wlc1986 2010-07-20
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厉害，还真不知道有这么回事。调试版都过关了，那应该问题不大，关掉这功能，确实不错。
BlueMap 2010-07-20
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很少用，接分。。。
jameshooo 2010-07-19
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很少用STL，接分吧
sevencat 2010-07-19
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这个很恶心的，有时候能非常强大的降低你的程序的速度。
webcq1999 2010-07-19
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谢谢，接分。
fishion 2010-07-19
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不知道
sunlin7 2010-07-19
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还真的没有留意到呢~~
苏克贝塔03 2010-07-19
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都下班了，接分的不多。。。
oyljerry 2010-07-19
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^_^，多谢分享
woai1075 2010-07-19
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学习 接分
adamwyb 2010-07-19
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学习接分
icefairy 2010-07-19
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jf 学习了
chenyu2202863 2010-07-19
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看来放错了坛子~
chenyu2202863 2010-07-19
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三分贴，没人要？
Formular1 2010-07-19
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不用stl
dulvtianya 2010-07-19
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学习并接分
stonewater 2010-07-19
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学习了
加载更多回复（7）
Git-2.21.0-64 for windows
Git 2.23 Release Notes
======================
Updates since v2.22
-------------------
Backward compatibility note
* The "--base" option of "format-patch" computed the patch-ids for
prerequisite patches in an unstable way, which has been updated to
compute in a way that is compatible with "git patch-id --stable".
* The "git log" command by default behaves as if the --mailmap option
was given.
UI, Workflows & Features
* The "git fast-export/import" pair has been taught to handle commits
with log messages in encoding other than UTF-8 better.
* In recent versions of Git, per-worktree refs are exposed in
refs/worktrees// hierarchy, which means that worktree names
must be a valid refname component. The code now sanitizes the names
given to worktrees, to make sure these refs are well-formed.
* "git merge" learned "--quit" option that cleans up the in-progress
merge while leaving the working tree and the index still in a mess.
* "git format-patch" learns a configuration to set the default for
its --notes= option.
* The code to show args with potential typo that cannot be
interpreted as a commit-ish has been improved.
* "git clone --recurse-submodules" learned to set up the submodules
to ignore commit object names recorded in the superproject gitlink
and instead use the commits that happen to be at the tip of the
remote-tracking branches from the get-go, by passing the new
"--remote-submodules" option.
* The pattern "git diff/grep" use to extract funcname and words
boundary for Matlab has been extend to cover Octave, which is more
or less equivalent.
* "git help git" was hard to discover (well, at least for some
people).
* The pattern "git diff/grep" use to extract funcname and words
boundary for Rust has been added.
* "git status" can be told a non-standard default value for the
"--[no-]ahead-behind" option with a new configuration variable
status.aheadBehind.
* "git fetch" and "git pull" reports when a fetch results in
non-fast-forward updates to let the user notice unusual situation.
The commands learned "--no-show-forced-updates" option to disable
this safety feature.
* Two new commands "git switch" and "git restore" are introduced to
split "checking out a branch to work on advancing its history" and
"checking out paths out of the index and/or a tree-ish to work on
advancing the current history" out of the single "git checkout"
command.
* "git branch --list" learned to always output the detached HEAD as
the first item (when the HEAD is detached, of course), regardless
of the locale.
* The conditional inclusion mechanism learned to base the choice on
the branch the HEAD currently is on.
* "git rev-list --objects" learned the "--no-object-names" option to
squelch the path to the object that is used as a grouping hint for
pack-objects.
* A new tag.gpgSign configuration variable turns "git tag -a" into
"git tag -s".
* "git multi-pack-index" learned expire and repack subcommands.
* "git blame" learned to "ignore" commits in the history, whose
effects (as well as their presence) get ignored.
* "git cherry-pick/revert" learned a new "--skip" action.
* The tips of refs from the alternate object store can be used as
starting point for reachability computation now.
* Extra blank lines in "git status" output have been reduced.
* The commits in a repository can be described by multiple
commit-graph files now, which allows the commit-graph files to be
updated incrementally.
* "git range-diff" output has been tweaked for easier identification
of which part of what file the patch shown is about.
Performance, Internal Implementation, Development Support etc.
* Update supporting parts of "git rebase" to remove code that should
no longer be used.
* Developer support to emulate unsatisfied prerequisites in tests to
ensure that the remainder of the tests still succeeds when tests
with prerequisites are skipped.
* "git update-server-info" learned not to rewrite the file with the
same contents.
* The way of specifying the path to find dynamic libraries at runtime
has been simplified. The old default to pass -R/path/to/dir has been
replaced with the new default to pass -Wl,-rpath,/path/to/dir,
which is the more recent GCC uses. Those who need to build with an
old GCC can still use "CC_LD_DYNPATH=-R"
* Prepare use of reachability index in topological walker that works
on a range (A..B).
* A new tutorial targeting specifically aspiring git-core
developers has been added.
* Auto-detect how to tell HP-UX aCC where to use dynamically linked
libraries from at runtime.
* "git mergetool" and its tests now spawn fewer subprocesses.
* Dev support update to help tracing out tests.
* Support to build with MSVC has been updated.
* "git fetch" that grabs from a group of remotes learned to run the
auto-gc only once at the very end.
* A handful of Windows build patches have been upstreamed.
* The code to read state files used by the sequencer machinery for
"git status" has been made more robust against a corrupt or stale
state files.
* "git for-each-ref" with multiple patterns have been optimized.
* The tree-walk API learned to pass an in-core repository
instance throughout more codepaths.
* When one step in multi step cherry-pick or revert is reset or
committed, the command line prompt script failed to notice the
current status, which has been improved.
* Many GIT_TEST_* environment variables control various aspects of
how our tests are run, but a few followed "non-empty is true, empty
or unset is false" while others followed the usual "there are a few
ways to spell true, like yes, on, etc., and also ways to spell
false, like no, off, etc." convention.
* Adjust the dir-iterator API and apply it to the local clone
optimization codepath.
* We have been trying out a few language features outside c89; the
coding guidelines document did not talk about them and instead had
a blanket ban against them.
* A test helper has been introduced to optimize preparation of test
repositories with many simple commits, and a handful of test
scripts have been updated to use it.
Fixes since v2.22
-----------------
* A relative pathname given to "git init --template= "
ought to be relative to the directory "git init" gets invoked in,
but it instead was made relative to the repository, which has been
corrected.
* "git worktree add" used to fail when another worktree connected to
the same repository was corrupt, which has been corrected.
* The ownership rule for the file descriptor to fast-import remote
backend was mixed up, leading to an unrelated file descriptor getting
closed, which has been fixed.
* A "merge -c" instruction during "git rebase --rebase-merges" should
give the user a chance to edit the log message, even when there is
otherwise no need to create a new merge and replace the existing
one (i.e. fast-forward instead), but did not. Which has been
corrected.
* Code cleanup and futureproof.
* More parameter validation.
* "git update-server-info" used to leave stale packfiles in its
output, which has been corrected.
* The server side support for "git fetch" used to show incorrect
value for the HEAD symbolic ref when the namespace feature is in
use, which has been corrected.
* "git am -i --resolved" segfaulted after trying to see a commit as
if it were a tree, which has been corrected.
* "git bundle verify" needs to see if prerequisite objects exist in
the receiving repository, but the command did not check if we are
in a repository upfront, which has been corrected.
* "git merge --squash" is designed to update the working tree and the
index without creating the commit, and this cannot be countermanded
by adding the "--commit" option; the command now refuses to work
when both options are given.
* The data collected by fsmonitor was not properly written back to
the on-disk index file, breaking t7519 tests occasionally, which
has been corrected.
* Update to Unicode 12.1 width table.
* The command line to invoke a "git cat-file" command from inside
"git p4" was not properly quoted to protect a caret and running a
broken command on Windows, which has been corrected.
* "git request-pull" learned to warn when the ref we ask them to pull
from in the local repository and in the published repository are
different.
* When creating a partial clone, the object filtering criteria is
recorded for the origin of the clone, but this incorrectly used a
hardcoded name "origin" to name that remote; it has been corrected
to honor the "--origin " option.
* "git fetch" into a lazy clone forgot to fetch base objects that are
necessary to complete delta in a thin packfile, which has been
corrected.
* The filter_data used in the list-objects-filter (which manages a
lazily sparse clone repository) did not use the dynamic array API
correctly---'nr' is supposed to point at one past the last element
of the array in use. This has been corrected.
* The description about slashes in gitignore patterns (used to
indicate things like "anchored to this level only" and "only
matches directories") has been revamped.
* The URL decoding code has been updated to avoid going past the end
of the string while parsing %-- sequence.
* The list of for-each like macros used by clang-format has been
updated.
* "git branch --list" learned to show branches that are checked out
in other worktrees connected to the same repository prefixed with
'+', similar to the way the currently checked out branch is shown
with '*' in front.
(merge 6e9381469e nb/branch-show-other-worktrees-head later to maint).
* Code restructuring during 2.20 period broke fetching tags via
"import" based transports.
* The commit-graph file is now part of the "files that the runtime
may keep open file descriptors on, all of which would need to be
closed when done with the object store", and the file descriptor to
an existing commit-graph file now is closed before "gc" finalizes a
new instance to replace it.
* "git checkout -p" needs to selectively apply a patch in reverse,
which did not work well.
* Code clean-up to avoid signed integer wraparounds during binary search.
* "git interpret-trailers" always treated '#' as the comment
character, regardless of core.commentChar setting, which has been
corrected.
* "git stash show 23" used to work, but no more after getting
rewritten in C; this regression has been corrected.
* "git rebase --abort" used to leave refs/rewritten/ when concluding
"git rebase -r", which has been corrected.
* An incorrect list of options was cached after command line
completion failed (e.g. trying to complete a command that requires
a repository outside one), which has been corrected.
* The code to parse scaled numbers out of configuration files has
been made more robust and also easier to follow.
* The codepath to compute delta islands used to spew progress output
without giving the callers any way to squelch it, which has been
fixed.
* Protocol capabilities that go over wire should never be translated,
but it was incorrectly marked for translation, which has been
corrected. The output of protocol capabilities for debugging has
been tweaked a bit.
* Use "Erase in Line" CSI sequence that is already used in the editor
support to clear cruft in the progress output.
* "git submodule foreach" did not protect command line options passed
to the command to be run in each submodule correctly, when the
"--recursive" option was in use.
* The configuration variable rebase.rescheduleFailedExec should be
effective only while running an interactive rebase and should not
affect anything when running a non-interactive one, which was not
the case. This has been corrected.
* The "git clone" documentation refers to command line options in its
description in the short form; they have been replaced with long
forms to make them more recognisable.
* Generation of pack bitmaps are now disabled when .keep files exist,
as these are mutually exclusive features.
(merge 7328482253 ew/repack-with-bitmaps-by-default later to maint).
* "git rm" to resolve a conflicted path leaked an internal message
"needs merge" before actually removing the path, which was
confusing. This has been corrected.
* "git stash --keep-index" did not work correctly on paths that have
been removed, which has been fixed.
(merge b932f6a5e8 tg/stash-keep-index-with-removed-paths later to maint).
* Window 7 update ;-)
* A codepath that reads from GPG for signed object verification read
past the end of allocated buffer, which has been fixed.
* "git clean" silently skipped a path when it cannot lstat() it; now
it gives a warning.
* "git push --atomic" that goes over the transport-helper (namely,
the smart http transport) failed to prevent refs to be pushed when
it can locally tell that one of the ref update will fail without
having to consult the other end, which has been corrected.
* The internal diff machinery can be made to read out of bounds while
looking for --function-context line in a corner case, which has been
corrected.
(merge b777f3fd61 jk/xdiff-clamp-funcname-context-index later to maint).
* Other code cleanup, docfix, build fix, etc.
(merge fbec05c210 cc/test-oidmap later to maint).
(merge 7a06fb038c jk/no-system-includes-in-dot-c later to maint).
(merge 81ed2b405c cb/xdiff-no-system-includes-in-dot-c later to maint).
(merge d61e6ce1dd sg/fsck-config-in-doc later to maint).
