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Size: 2642
Comment: Don't constantly evaluate end() in loops
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| [[http://clang.llvm.org/extra/clang-tidy/index.html|Clang-Tidy — Extra Clang Tools 3.9 documentation]] Use: {{{ clang-tidy -checks='*' main.cpp -- -std=c++11 }}} [[http://clang.llvm.org/docs/ClangFormat.html|ClangFormat]]: auto-formats C++ code * [[https://github.com/andrewseidl/githook-clang-format|Git hook running clang-format]]. Don't use this! |
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| == Formatting == [[http://clang.llvm.org/docs/ClangFormat.html|ClangFormat]]: auto-formats C++ code * [[https://github.com/andrewseidl/githook-clang-format|Git hook running clang-format]]. Don't use this! |
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| * [[http://clang.llvm.org/extra/clang-tidy/index.html|Clang-Tidy]]: C/C++ linting tool, à la Google's cpplint. {{{ clang-tidy -checks='*' *.cpp -- -std=c++11 }}} |
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| # Highest severity | # Highest severity warnings only (i.e. memory leaks, etc) |
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== Stuff I never remember == === Unnecessary copies w/ `auto` === Beware unncessary copies w/ `auto`; default semantics is to make a copy. {{{#!highlight c++ numbers=off // Typically there's no reason to copy. for (const auto &Val : Container) { observe(Val); } for (auto &Val : Container) { Val.change(); } // Remove the reference if you really want a new copy. for (auto Val : Container) { Val.change(); saveSomewhere(Val); } // Copy pointers, but make it clear that they're pointers. for (const auto *Ptr : Container) { observe(*Ptr); } for (auto *Ptr : Container) { Ptr->change(); } }}} === Don't evaluate `end()` in loops === {{{#!highlight c++ numbers=off // BAD BasicBlock *BB = ... for (BasicBlock::iterator I = BB->begin(); I != BB->end(); ++I) // ... use I ... // GOOD (unless you are mutating BB; use the above loop if you are, and document you are doing so) BasicBlock *BB = ... for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) // ... use I ... }}} |
C++ style guides
Formatting
ClangFormat: auto-formats C++ code
Git hook running clang-format. Don't use this!
Static analysis tools
Clang-Tidy: C/C++ linting tool, à la Google's cpplint.
clang-tidy -checks='*' *.cpp -- -std=c++11
Clang Static Analyzer: sets CC and CXX to use alternate compiler to do analysis
# Highest severity warnings only (i.e. memory leaks, etc)
cppcheck --enable=all *.cpp
# Everything except style-related linting
cppcheck --enable=warning,performance,portability,information,missingInclude \
--std=c++11 --library=std.cfg --verbose --quiet \
*.cpp
Overview articles:
Stuff I never remember
Unnecessary copies w/ `auto`
Beware unncessary copies w/ auto; default semantics is to make a copy.
// Typically there's no reason to copy.
for (const auto &Val : Container) { observe(Val); }
for (auto &Val : Container) { Val.change(); }
// Remove the reference if you really want a new copy.
for (auto Val : Container) { Val.change(); saveSomewhere(Val); }
// Copy pointers, but make it clear that they're pointers.
for (const auto *Ptr : Container) { observe(*Ptr); }
for (auto *Ptr : Container) { Ptr->change(); }
Don't evaluate `end()` in loops
// BAD
BasicBlock *BB = ...
for (BasicBlock::iterator I = BB->begin(); I != BB->end(); ++I)
// ... use I ...
// GOOD (unless you are mutating BB; use the above loop if you are, and document you are doing so)
BasicBlock *BB = ...
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
// ... use I ...
