gecko-dev/build/clang-plugin/MustUseChecker.cpp

64 lines
2.3 KiB
C++

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "MustUseChecker.h"
#include "CustomMatchers.h"
#include "CustomTypeAnnotation.h"
CustomTypeAnnotation MustUse =
CustomTypeAnnotation("moz_must_use_type", "must-use");
void MustUseChecker::registerMatchers(MatchFinder* AstMatcher) {
AstMatcher->addMatcher(switchCase().bind("switchcase"), this);
AstMatcher->addMatcher(compoundStmt().bind("compound"), this);
AstMatcher->addMatcher(ifStmt().bind("if"), this);
AstMatcher->addMatcher(whileStmt().bind("while"), this);
AstMatcher->addMatcher(doStmt().bind("do"), this);
AstMatcher->addMatcher(forStmt().bind("for"), this);
AstMatcher->addMatcher(binaryOperator(binaryCommaOperator()).bind("bin"), this);
}
void MustUseChecker::check(
const MatchFinder::MatchResult &Result) {
if (auto SC = Result.Nodes.getNodeAs<SwitchCase>("switchcase")) {
handleUnusedExprResult(SC->getSubStmt());
}
if (auto C = Result.Nodes.getNodeAs<CompoundStmt>("compound")) {
for (const auto& S : C->body()) {
handleUnusedExprResult(S);
}
}
if (auto IF = Result.Nodes.getNodeAs<IfStmt>("if")) {
handleUnusedExprResult(IF->getThen());
handleUnusedExprResult(IF->getElse());
}
if (auto W = Result.Nodes.getNodeAs<WhileStmt>("while")) {
handleUnusedExprResult(W->getBody());
}
if (auto D = Result.Nodes.getNodeAs<DoStmt>("do")) {
handleUnusedExprResult(D->getBody());
}
if (auto F = Result.Nodes.getNodeAs<ForStmt>("for")) {
handleUnusedExprResult(F->getBody());
handleUnusedExprResult(F->getInit());
handleUnusedExprResult(F->getInc());
}
if (auto C = Result.Nodes.getNodeAs<BinaryOperator>("bin")) {
handleUnusedExprResult(C->getLHS());
}
}
void MustUseChecker::handleUnusedExprResult(const Stmt *Statement) {
const Expr *E = dyn_cast_or_null<Expr>(Statement);
if (E) {
E = E->IgnoreImplicit(); // Ignore ExprWithCleanup etc. implicit wrappers
QualType T = E->getType();
if (MustUse.hasEffectiveAnnotation(T) && !isIgnoredExprForMustUse(E)) {
diag(E->getLocStart(), "Unused value of must-use type %0",
DiagnosticIDs::Error) << T;
MustUse.dumpAnnotationReason(*this, T, E->getLocStart());
}
}
}