Improve template argument deduction for reference parameters when

deducing template arguments from a function call. Plus, add a bunch of
tests.

llvm-svn: 74301

2 files changed, 75 insertions, 0 deletions

diff --git a/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.call/p2.cpp b/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.call/p2.cpp
new file mode 100644
index 00000000000..6f27d363689
--- /dev/null
+++ b/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.call/p2.cpp
@@ -0,0 +1,31 @@
+// RUN: clang-cc -fsyntax-only -verify %s
+template<typename T> struct A { };
+
+// bullet 1
+template<typename T> A<T> f0(T* ptr);
+
+void test_f0_bullet1() {
+  int arr0[6];
+  A<int> a0 = f0(arr0);
+  const int arr1[] = { 1, 2, 3, 4, 5 };
+  A<const int> a1 = f0(arr1);
+}
+
+// bullet 2
+int g0(int, int);
+float g1(float);
+
+void test_f0_bullet2() {
+  A<int(int, int)> a0 = f0(g0);
+  A<float(float)> a1 = f0(g1);
+}
+
+// bullet 3
+struct X { };
+const X get_X();
+
+template<typename T> A<T> f1(T);
+
+void test_f1_bullet3() {
+  A<X> a0 = f1(get_X());
+}
diff --git a/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.call/p3.cpp b/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.call/p3.cpp
new file mode 100644
index 00000000000..18023523a9b
--- /dev/null
+++ b/clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.call/p3.cpp
@@ -0,0 +1,44 @@
+// RUN: clang-cc -fsyntax-only %s
+
+template<typename T> struct A { };
+
+// Top-level cv-qualifiers of P's type are ignored for type deduction.
+template<typename T> A<T> f0(const T);
+
+void test_f0(int i, const int ci) {
+  A<int> a0 = f0(i);
+  A<int> a1 = f0(ci);
+}
+
+// If P is a reference type, the type referred to by P is used for type 
+// deduction.
+template<typename T> A<T> f1(T&);
+
+void test_f1(int i, const int ci, volatile int vi) {
+  A<int> a0 = f1(i);
+  A<const int> a1 = f1(ci);
+  A<volatile int> a2 = f1(vi);
+}
+
+template<typename T, unsigned N> struct B { };
+template<typename T, unsigned N> B<T, N> g0(T (&array)[N]);
+
+void test_g0() {
+  int array0[5];
+  B<int, 5> b0 = g0(array0);
+  const int array1[] = { 1, 2, 3};
+  B<const int, 3> b1 = g0(array1);
+}
+
+//   - If the original P is a reference type, the deduced A (i.e., the type
+//     referred to by the reference) can be more cv-qualified than the 
+//     transformed A.
+template<typename T> A<T> f2(const T&);
+
+void test_f2(int i, const int ci, volatile int vi) {
+  A<int> a0 = f2(i);
+  A<int> a1 = f2(ci);
+  A<volatile int> a2 = f2(vi);
+}
+
+// FIXME: the next two bullets require a bit of effort.
\ No newline at end of file