In this article we compared different behavior of static, inline and static inline free functions in compiled binary.
All the following test was done under g++ 7.1.1 on Linux amd64, ELF64.
#pragma once
inline int only_inline() { return 42; }
static int only_static() { return 42; }
This profile achieves 50% - 80% release profile performance, while also provides a reasonable amount of safety checks and debugging support. This should also be the profile for your CI build.
-Og -Wall -Wextra -D_FORTIFY_SOURCE=2 -fstack-protector-strong -g -D_GLIBCXX_ASSERTIONS
Add the following target to your bookmark bar.
Remember to replace %24YOUR_TOKEN_HERE with your Github personal access token. The token could be acquired at Settings -> Developer Settings -> Personal Access Token and check public_repo permission.
javascript:(function()%7Bconst%20apiRequest%20%3D%20(src%2C%20param)%20%3D%3E%20fetch('https%3A%2F%2Fapi.github.com%2F'%20%2B%20src%2C%20Object.assign(%7Bheaders%3A%20%7B%20Accept%3A%20'application%2Fvnd.github.v3%2Bjson'%2C%20'Content-Type'%3A%20'application%2Fjson'%2C%20Authorization%3A%20'token%20%24YOUR_TOKEN_HERE'%20%7D%7D%2C%20param))%3BapiRequest('repos%2Fdyweb%2Fweekly%2Fissues').then(v%20%3D%3E%20v.json()).then(d%20%3D%3E%20d.filter(item%20%3D%3E%20item.labels.some(lab%20%3D%3E%20lab.name%20%3D%3D%3D%20'working'))%5B0%5D.number).then(issuenum%20%3D%3E%20%7Bconst%20url%20%3D%20'repos%2Fdyweb%2Fweekly%2Fissues%2F'%20%2B%20issuenum%20%2B%20'%2Fcomments'%3Bconst%20description%20%3D%20window.prompt('Please%20input%20your%20description%20of%20this%2| #include <bits/stdc++.h> | |
| /* | |
| https://codeforces.com/contest/1093/problem/E | |
| Convert all modification and query into single-point events (t, x, y). Initially sort by t, | |
| for each interval, recursively handle independent two parts. Then calc the interference | |
| between part one and two: only mod in part 1 can affect result in part 2. Therefore, we can | |
| sort part1 and 2 respectively by x, then process all mod event in part 1 and all query events in | |
| part 2 in a sort-merge-like way. The Y-dimension is maintained with a fenwick tree. | |
| In the end all elements will be sorted by x. |
C++ has a lot of dark corners. Unfortunately, sometimes we need to allow inexperienced developers to write some C++ code to meet the deadline. The intersection of the two cases often makes things worse: programmers used to delegate memory management to garbage collection tend to throw off new everywhere in the source, and those stuck with compile error will use every evil hack to get around with it. Code review is a feasible way to ensure code quality in this case, but a better choice is to restrict them into a relatively safe subset of the language.
In this article, I will show how to use clang-query and a simple script to restrict some unsafe behaviors in unsafe block/namespace using simple commands:
#include "common.hpp"
struct X {
int f: 2; // error: use of bit field without enclosing Unsafe
};
| <?xml version="1.0" encoding="UTF-8"?> | |
| <opml version="1.0"> | |
| <head> | |
| <title>Vic subscriptions in feedly Cloud</title> | |
| </head> | |
| <body> | |
| <outline text="news" title="news"> | |
| <outline type="rss" text="路透: 时事要闻" title="路透: 时事要闻" xmlUrl="http://cn.reuters.com/rssFeed/CNTopGenNews/" htmlUrl="http://cn.reuters.com"/> | |
| <outline type="rss" text="Washington Post: Breaking News, World, US, DC News & Analysis" title="Washington Post: Breaking News, World, US, DC News & Analysis" xmlUrl="http://www.washingtonpost.com/rss/homepage" htmlUrl="http://www.washingtonpost.com/pb/homepage/"/> |
CXXFLAGS="-ffast-math -fdevirtualize-speculatively -fassociative-math -freciprocal-math -fno-signed-zeros -fno-trapping-math -fipa-pta -mrecip=all -fgcse-sm -fgcse-las -fgcse-after-reload -march=native -ftree-vectorize -floop-interchange -floop-block -ftree-coalesce-vars -floop-nest-optimize -fgraphite-identity -ftree-loop-ivcanon -fivopts" LDFLAGS="-ffast-math -fdevirtualize-speculatively"
rendering time = 91ms
rendering time = 92ms
| set guiheadroom=-20 | |
| set shell=/bin/bash | |
| if &term =~ '^\(xterm\|screen\)$' && $COLORTERM == 'gnome-terminal' | |
| set t_Co=256 | |
| endif | |
| filetype on | |
| filetype plugin on | |
| set autoindent | |
| set nolazyredraw | |
| set number |
Two reasons:
cat /sys/block/sda/queue/schedulertl;dr:
| #!/bin/bash | |
| # Usage: | |
| # Assuming you are in ROOT/build | |
| # and ROOT contains conanfile.txt and CMakeLists.txt | |
| # ./install_dep_and_build [Debug|Release|RelWithDebInfo] | |
| # Prerequisite: | |
| # Make sure you have | |
| # [generators] |