Static analyzer fix: <rdar://problem/5880430> Switch on enum should not consider default case live if all enum values are covered
llvm-svn: 113457
diff --git a/clang/include/clang/AST/Expr.h b/clang/include/clang/AST/Expr.h
index 48130be..1f3a1ba 100644
--- a/clang/include/clang/AST/Expr.h
+++ b/clang/include/clang/AST/Expr.h
@@ -422,6 +422,10 @@
/// ParenExpr or ImplicitCastExprs, returning their operand.
Expr *IgnoreParenImpCasts();
+ const Expr *IgnoreParenImpCasts() const {
+ return const_cast<Expr*>(this)->IgnoreParenImpCasts();
+ }
+
/// IgnoreParenNoopCasts - Ignore parentheses and casts that do not change the
/// value (including ptr->int casts of the same size). Strip off any
/// ParenExpr or CastExprs, returning their operand.
diff --git a/clang/include/clang/Checker/PathSensitive/GRCoreEngine.h b/clang/include/clang/Checker/PathSensitive/GRCoreEngine.h
index 216ecac..bba59f5 100644
--- a/clang/include/clang/Checker/PathSensitive/GRCoreEngine.h
+++ b/clang/include/clang/Checker/PathSensitive/GRCoreEngine.h
@@ -422,6 +422,10 @@
iterator begin() { return iterator(Src->succ_rbegin()+1); }
iterator end() { return iterator(Src->succ_rend()); }
+ const SwitchStmt *getSwitch() const {
+ return llvm::cast<SwitchStmt>(Src->getTerminator());
+ }
+
ExplodedNode* generateCaseStmtNode(const iterator& I, const GRState* State);
ExplodedNode* generateDefaultCaseNode(const GRState* State,
diff --git a/clang/lib/Checker/GRExprEngine.cpp b/clang/lib/Checker/GRExprEngine.cpp
index 1c8a2d6..c11785a 100644
--- a/clang/lib/Checker/GRExprEngine.cpp
+++ b/clang/lib/Checker/GRExprEngine.cpp
@@ -1561,9 +1561,24 @@
} while (true);
}
- // If we reach here, than we know that the default branch is
- // possible.
- if (defaultIsFeasible) builder.generateDefaultCaseNode(DefaultSt);
+ if (!defaultIsFeasible)
+ return;
+
+ // If we have switch(enum value), the default branch is not
+ // feasible if all of the enum constants not covered by 'case:' statements
+ // are not feasible values for the switch condition.
+ //
+ // Note that this isn't as accurate as it could be. Even if there isn't
+ // a case for a particular enum value as long as that enum value isn't
+ // feasible then it shouldn't be considered for making 'default:' reachable.
+ const SwitchStmt *SS = builder.getSwitch();
+ const Expr *CondExpr = SS->getCond()->IgnoreParenImpCasts();
+ if (CondExpr->getType()->getAs<EnumType>()) {
+ if (SS->isAllEnumCasesCovered())
+ return;
+ }
+
+ builder.generateDefaultCaseNode(DefaultSt);
}
void GRExprEngine::ProcessCallEnter(GRCallEnterNodeBuilder &B) {