First part of PR9968: the __range variable in a dependent C++11 for-range statement is implicitly used by that statement.
llvm-svn: 133572
diff --git a/clang/lib/Sema/SemaStmt.cpp b/clang/lib/Sema/SemaStmt.cpp
index 9af9c8d..0ba4f99 100644
--- a/clang/lib/Sema/SemaStmt.cpp
+++ b/clang/lib/Sema/SemaStmt.cpp
@@ -1406,6 +1406,9 @@
if (LoopVar->isInvalidDecl())
NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
}
+ } else {
+ // The range is implicitly used as a placeholder when it is dependent.
+ RangeVar->setUsed();
}
return Owned(new (Context) CXXForRangeStmt(RangeDS,
diff --git a/clang/test/SemaCXX/for-range-unused.cpp b/clang/test/SemaCXX/for-range-unused.cpp
new file mode 100644
index 0000000..7e26c78
--- /dev/null
+++ b/clang/test/SemaCXX/for-range-unused.cpp
@@ -0,0 +1,22 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s -std=c++0x -Wunused
+
+// PR9968: We used to warn that __range is unused in a dependent for-range.
+
+template <typename T>
+ struct Vector {
+ void doIt() {
+ // FIXME: PR10168: Only warn once for this!
+ int a; // expected-warning 2{{unused variable 'a'}}
+
+ for (auto& e : elements)
+ ;
+ }
+
+ T elements[10];
+ };
+
+
+int main(int, char**) {
+ Vector<int> vector;
+ vector.doIt(); // expected-note {{requested here}}
+}