From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Wed, 21 Dec 2011 00:25:33 +0000 (+0000)
Subject: C++ constant expression handling: eagerly instantiate static const integral data
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=3e9ea0b8cd7c4691d62e385245556be5fded58a7;p=clang

C++ constant expression handling: eagerly instantiate static const integral data
members of class templates so that their values can be used in ICEs. This
required reverting r105465, to get such instantiated members to be included in
serialized ASTs.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147023 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 65439032f2..3a61fe5066 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -9526,7 +9526,12 @@ void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) {
         // This is a modification of an existing AST node. Notify listeners.
         if (ASTMutationListener *L = getASTMutationListener())
           L->StaticDataMemberInstantiated(Var);
-        PendingInstantiations.push_back(std::make_pair(Var, Loc));
+        QualType T = Var->getType();
+        if (T.isConstQualified() && !T.isVolatileQualified() &&
+            T->isIntegralOrEnumerationType())
+          InstantiateStaticDataMemberDefinition(Loc, Var);
+        else
+          PendingInstantiations.push_back(std::make_pair(Var, Loc));
       }
     }
 
diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index b2208b63c8..53adf68cd9 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -359,8 +359,7 @@ Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D) {
   SemaRef.CheckVariableDeclaration(Var, Previous);
 
   if (D->isOutOfLine()) {
-    if (!D->isStaticDataMember())
-      D->getLexicalDeclContext()->addDecl(Var);
+    D->getLexicalDeclContext()->addDecl(Var);
     Owner->makeDeclVisibleInContext(Var);
   } else {
     Owner->addDecl(Var);
diff --git a/test/PCH/chain-cxx.cpp b/test/PCH/chain-cxx.cpp
index c42ee7d39e..0d50e61c5a 100644
--- a/test/PCH/chain-cxx.cpp
+++ b/test/PCH/chain-cxx.cpp
@@ -38,9 +38,12 @@ template<typename T> struct TestBaseSpecifiers2 : TestBaseSpecifiers<T> { };
 template <typename T>
 struct TS3 {
   static const int value = 0;
+  static const int value2;
 };
 template <typename T>
 const int TS3<T>::value;
+template <typename T>
+const int TS3<T>::value2 = 1;
 // Instantiate struct, but not value.
 struct instantiate : TS3<int> {};
 
@@ -96,8 +99,9 @@ struct TestBaseSpecifiers4 : TestBaseSpecifiers3 { };
 struct A { };
 struct B : A { };
 
-// Instantiate TS3's member.
+// Instantiate TS3's members.
 static const int ts3m1 = TS3<int>::value;
+extern int arr[TS3<int>::value2];
 
 // Redefinition of typedef
 typedef int Integer;
@@ -132,6 +136,7 @@ void test() {
 
 // Should have remembered that there is a definition.
 static const int ts3m2 = TS3<int>::value;
+int arr[TS3<int>::value2];
 
 //===----------------------------------------------------------------------===//
 #endif
diff --git a/test/SemaTemplate/instantiate-declref-ice.cpp b/test/SemaTemplate/instantiate-declref-ice.cpp
index 0f3c08b056..49b1b63f51 100644
--- a/test/SemaTemplate/instantiate-declref-ice.cpp
+++ b/test/SemaTemplate/instantiate-declref-ice.cpp
@@ -31,4 +31,4 @@ struct X1 {
 template<typename T>
 const unsigned X1<T>::value = sizeof(T);
 
-int array3[X1<int>::value == sizeof(int)? 1 : -1]; // expected-error{{variable length array declaration not allowed at file scope}}
+int array3[X1<int>::value == sizeof(int)? 1 : -1];