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Comment: Don't constantly evaluate end() in loops
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=== Use `const` iterators if not mutating a structure === Expanding on the above: {{{#!highlight c++ numbers=off BasicBlock *BB = ... for (BasicBlock::const_iterator I = BB->cbegin(), E = BB->cend(); 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 ...
Use `const` iterators if not mutating a structure
Expanding on the above:
BasicBlock *BB = ...
for (BasicBlock::const_iterator I = BB->cbegin(), E = BB->cend(); I != E; ++I)
// ... use I ...
