commit 34b41d939a1328f484511c6002ba2456db879a29
author Richard Smith <richard-llvm@metafoo.co.uk> Sun Feb 20 03:19:35 2011 +0000
committer Richard Smith <richard-llvm@metafoo.co.uk> Sun Feb 20 03:19:35 2011 +0000
tree 9631c2ce7dde0b9c680fe463d5718d0cb8f92e45
parent 9ed9a250180f19b2c44df83a196fc3a2ac82f817

Implement the C++0x deduced 'auto' feature.

This fixes PR 8738, 9060 and 9132.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@126069 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/SemaDeclCXX.cpp

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 2e6c4c8..e8abab8 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -1073,7 +1073,8 @@
   assert((Name || isInstField) && "No identifier for non-field ?");
 
   if (Init)
-    AddInitializerToDecl(Member, Init, false);
+    AddInitializerToDecl(Member, Init, false,
+                         DS.getTypeSpecType() == DeclSpec::TST_auto);
   if (Deleted) // FIXME: Source location is not very good.
     SetDeclDeleted(Member, D.getSourceRange().getBegin());
 
@@ -5953,7 +5954,8 @@
 void Sema::AddCXXDirectInitializerToDecl(Decl *RealDecl,
                                          SourceLocation LParenLoc,
                                          MultiExprArg Exprs,
-                                         SourceLocation RParenLoc) {
+                                         SourceLocation RParenLoc,
+                                         bool TypeMayContainAuto) {
   assert(Exprs.size() != 0 && Exprs.get() && "missing expressions");
 
   // If there is no declaration, there was an error parsing it.  Just ignore
@@ -5968,6 +5970,37 @@
     return;
   }
 
+  // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for.
+  if (TypeMayContainAuto && VDecl->getType()->getContainedAutoType()) {
+    VDecl->setParsingAutoInit(false);
+
+    // FIXME: n3225 doesn't actually seem to indicate this is ill-formed
+    if (Exprs.size() > 1) {
+      Diag(Exprs.get()[1]->getSourceRange().getBegin(),
+           diag::err_auto_var_init_multiple_expressions)
+        << VDecl->getDeclName() << VDecl->getType()
+        << VDecl->getSourceRange();
+      RealDecl->setInvalidDecl();
+      return;
+    }
+
+    Expr *Init = Exprs.get()[0];
+    QualType DeducedType;
+    if (!DeduceAutoType(VDecl->getType(), Init, DeducedType)) {
+      Diag(VDecl->getLocation(), diag::err_auto_var_deduction_failure)
+        << VDecl->getDeclName() << VDecl->getType() << Init->getType()
+        << Init->getSourceRange();
+      RealDecl->setInvalidDecl();
+      return;
+    }
+    VDecl->setType(DeducedType);
+
+    // If this is a redeclaration, check that the type we just deduced matches
+    // the previously declared type.
+    if (VarDecl *Old = VDecl->getPreviousDeclaration())
+      MergeVarDeclTypes(VDecl, Old);
+  }
+
   // We will represent direct-initialization similarly to copy-initialization:
   //    int x(1);  -as-> int x = 1;
   //    ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c);