Fix -Wunused-value to not warn on expressions that have unresolved lookups due
to dependent arguments.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166468 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index 694325a..3c8cbb5 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -1950,6 +1950,11 @@
return false;
}
+ // If we don't know precisely what we're looking at, let's not warn.
+ case UnresolvedLookupExprClass:
+ case CXXUnresolvedConstructExprClass:
+ return false;
+
case CXXTemporaryObjectExprClass:
case CXXConstructExprClass:
return false;
diff --git a/test/SemaCXX/unused.cpp b/test/SemaCXX/unused.cpp
index b9877a1..fbaf8c8 100644
--- a/test/SemaCXX/unused.cpp
+++ b/test/SemaCXX/unused.cpp
@@ -46,3 +46,18 @@
int(1); // expected-warning {{expression result unused}}
}
}
+
+// Test that constructing an object (which may have side effects) with
+// constructor arguments which are dependent doesn't produce an unused value
+// warning.
+namespace UnresolvedLookup {
+ struct Foo {
+ Foo(int i, int j);
+ };
+ template <typename T>
+ struct Bar {
+ void f(T t) {
+ Foo(t, 0); // no warning
+ }
+ };
+}