constexpr: Disable checking of constructor member initializer lists for

constexpr constructor templates. Such checking is optional, and currently hard
to get right since clang doesn't generate implicit member initializers until
instantiation (even for non-dependent members).

This is needed for clang to accept libstdc++ from g++4.6 in c++0x mode.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@141547 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 247d8dc5bba82cf0b215c9a08b129cdff5dad1c6..4f9c0493c674890e8c9c32e883aff377b1d12344 100644 (file)
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -902,7 +902,8 @@ bool Sema::CheckConstexprFunctionBody(const FunctionDecl *Dcl, Stmt *Body) {
         Diag(Dcl->getLocation(), diag::err_constexpr_union_ctor_no_init);
         return false;
       }
-    } else if (!Constructor->isDelegatingConstructor()) {
+    } else if (!Constructor->isDependentContext() &&
+               !Constructor->isDelegatingConstructor()) {
       assert(RD->getNumVBases() == 0 && "constexpr ctor with virtual bases");
 
       // Skip detailed checking if we have enough initializers, and we would

diff --git a/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p4.cpp b/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p4.cpp
index 4594f6cdb063e4730eb47d6fbece8e89274a4aaa..804ea9abddcf6b9e1cece0604c19f21c726394cd 100644 (file)
--- a/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p4.cpp
+++ b/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p4.cpp
@@ -150,6 +150,44 @@ struct AnonMembers {
   constexpr AnonMembers(int(&)[6]) {} // expected-error {{constexpr constructor must initialize all members}}
 };
 
+template<typename T> using Int = int;
+template<typename T>
+struct TemplateInit {
+  T a;
+  int b; // desired-note {{not initialized}}
+  Int<T> c; // desired-note {{not initialized}}
+  struct {
+    T d;
+    int e; // desired-note {{not initialized}}
+    Int<T> f; // desired-note {{not initialized}}
+  };
+  struct {
+    Literal l;
+    Literal m;
+    Literal n[3];
+  };
+  union { // desired-note {{not initialized}}
+    T g;
+    T h;
+  };
+  // FIXME: This is ill-formed (no diagnostic required). We should diagnose it.
+  constexpr TemplateInit() {} // desired-error {{must initialize all members}}
+};
+template<typename T> struct TemplateInit2 {
+  Literal l;
+  constexpr TemplateInit2() {} // ok
+};
+
+template<typename T> struct weak_ptr {
+  constexpr weak_ptr() : p(0) {}
+  T *p;
+};
+template<typename T> struct enable_shared_from_this {
+  weak_ptr<T> weak_this;
+  constexpr enable_shared_from_this() {} // ok
+};
+constexpr int f(enable_shared_from_this<int>);
+
 // - every constructor involved in initializing non-static data members and base
 //   class sub-objects shall be a constexpr constructor.
 //