Implement and test aggregate initialization in C++. Major changes:

  - Support initialization of reference members; complain if any
  reference members are left uninitialized.
  - Use C++ copy-initialization for initializing each element (falls
  back to constraint checking in C)
  - Make sure we diagnose when one tries to provide an initializer
  list for a non-aggregate.
  - Don't complain about empty initializers in C++ (they are permitted)
  - Unrelated but necessary: don't bother trying to convert the
  decl-specifier-seq to a type when we're dealing with a C++
  constructor, destructor, or conversion operator; it results in
  spurious warnings.

llvm-svn: 63431

1 files changed, 107 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/dcl_init_aggr.cpp b/clang/test/SemaCXX/dcl_init_aggr.cpp
new file mode 100644
index 00000000000..d8a41805365
--- /dev/null
+++ b/clang/test/SemaCXX/dcl_init_aggr.cpp
@@ -0,0 +1,107 @@
+// RUN: clang -fsyntax-only -pedantic -verify %s
+// C++ [dcl.init.aggr]p2
+struct A { 
+  int x;
+  struct B { 
+    int i;
+    int j;
+  } b; 
+} a1 = { 1, { 2, 3 } };
+
+struct NonAggregate {
+  NonAggregate();
+
+  int a, b;
+};
+NonAggregate non_aggregate_test = { 1, 2 }; // expected-error{{initialization of non-aggregate type 'struct NonAggregate' with an initializer list}}
+
+NonAggregate non_aggregate_test2[2] = { { 1, 2 }, { 3, 4 } }; // expected-error{{initialization of non-aggregate type 'struct NonAggregate' with an initializer list}}
+
+
+// C++ [dcl.init.aggr]p3
+A a_init = A(); 
+
+// C++ [dcl.init.aggr]p4
+int x[] = { 1, 3, 5 };
+int x_sizecheck[(sizeof(x) / sizeof(int)) == 3? 1 : -1];
+int x2[] = { }; // expected-warning{{zero size arrays are an extension}}
+
+// C++ [dcl.init.aggr]p5
+struct StaticMemberTest {
+  int i;
+  static int s;
+  int *j;
+} smt = { 1, &smt.i };
+
+// C++ [dcl.init.aggr]p6
+char cv[4] = { 'a', 's', 'd', 'f', 0 }; // expected-warning{{excess elements in array initializer}}
+
+// C++ [dcl.init.aggr]p7
+struct TooFew { int a; char* b; int c; }; 
+TooFew too_few = { 1, "asdf" }; // okay
+
+// C++ [dcl.init.aggr]p8
+struct Empty { };
+struct EmptyTest {
+  Empty s;
+  int i;
+} empty_test = { { }, 3 };
+
+EmptyTest empty_test2 = { 3 }; // expected-error{{initializer for aggregate with no elements requires explicit braces}}
+
+struct NonEmpty { 
+  int a;
+  Empty empty;
+};
+struct NonEmptyTest {
+  NonEmpty a, b;
+} non_empty_test = { { }, { } };
+
+// C++ [dcl.init.aggr]p9
+struct HasReference {
+  int i;
+  int &j; // expected-note{{uninitialized reference member is here}}
+};
+int global_int;
+HasReference r1 = { 1, global_int };
+HasReference r2 = { 1 } ; // expected-error{{initialization leaves reference member of type 'int &' uninitialized}}
+
+// C++ [dcl.init.aggr]p10
+// Note: the behavior here is identical to C
+int xs[2][2] = { 3, 1, 4, 2 };
+float y[4][3] = { { 1 }, { 2 }, { 3 }, { 4 } };
+
+// C++ [dcl.init.aggr]p11
+// Note: the behavior here is identical to C
+float y2[4][3] = { { 1, 3, 5 }, { 2, 4, 6 }, { 3, 5, 7 } };
+float same_as_y2[4][3] = { 1, 3, 5, 2, 4, 6, 3, 5, 7 };
+
+// C++ [dcl.init.aggr]p12
+struct A2 { 
+  int i;
+  operator int *();
+}; 
+struct B2 {
+  A2 a1, a2; 
+  int *z;
+}; 
+struct C2 {
+  operator A2();
+};
+struct D2 {
+  operator int();
+};
+A2 a2;
+C2 c2; 
+D2 d2;
+B2 b2 = { 4, a2, a2 };
+B2 b2_2 = { 4, d2, 0 };
+// FIXME: B2 b2_3 = { c2, a2, a2 };
+
+// C++ [dcl.init.aggr]p15:
+union u { int a; char* b; };
+u u1 = { 1 }; 
+u u2 = u1; 
+u u3 = 1; // expected-error{{cannot initialize 'u3' with an rvalue of type 'int'}}
+u u4 = { 0, "asdf" };  // expected-warning{{excess elements in array initializer}}
+u u5 = { "asdf" }; // expected-error{{incompatible type initializing 'char const [5]', expected 'int'}}