-Wunsequenced: if the LHS of an &&, || or ?: is not constant, check for
unsequenced operations in the RHS. We don't compare the RHS with the rest of
the expression yet; such checks will need care to avoid diagnosing unsequenced
operations which are both in conditionally-evaluated subexpressions which
actually can't occur together, such as in '(b && ++x) + (!b && ++x)'.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@172760 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 69500ae..1b9239c 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -5507,9 +5507,18 @@
bool Result;
if (!BO->getLHS()->isValueDependent() &&
- BO->getLHS()->EvaluateAsBooleanCondition(Result, SemaRef.Context) &&
- !Result)
- Visit(BO->getRHS());
+ BO->getLHS()->EvaluateAsBooleanCondition(Result, SemaRef.Context)) {
+ if (!Result)
+ Visit(BO->getRHS());
+ } else {
+ // Check for unsequenced operations in the RHS, treating it as an
+ // entirely separate evaluation.
+ //
+ // FIXME: If there are operations in the RHS which are unsequenced
+ // with respect to operations outside the RHS, and those operations
+ // are unconditionally evaluated, diagnose them.
+ SequenceChecker(SemaRef, BO->getRHS());
+ }
}
void VisitBinLAnd(BinaryOperator *BO) {
{
@@ -5519,9 +5528,12 @@
bool Result;
if (!BO->getLHS()->isValueDependent() &&
- BO->getLHS()->EvaluateAsBooleanCondition(Result, SemaRef.Context) &&
- Result)
- Visit(BO->getRHS());
+ BO->getLHS()->EvaluateAsBooleanCondition(Result, SemaRef.Context)) {
+ if (Result)
+ Visit(BO->getRHS());
+ } else {
+ SequenceChecker(SemaRef, BO->getRHS());
+ }
}
// Only visit the condition, unless we can be sure which subexpression will
@@ -5534,6 +5546,10 @@
if (!CO->getCond()->isValueDependent() &&
CO->getCond()->EvaluateAsBooleanCondition(Result, SemaRef.Context))
Visit(Result ? CO->getTrueExpr() : CO->getFalseExpr());
+ else {
+ SequenceChecker(SemaRef, CO->getTrueExpr());
+ SequenceChecker(SemaRef, CO->getFalseExpr());
+ }
}
void VisitCXXConstructExpr(CXXConstructExpr *CCE) {