Represent C++ direct initializers as ParenListExprs before semantic analysis

instead of having a special-purpose function.

- ActOnCXXDirectInitializer, which was mostly duplication of
  AddInitializerToDecl (leading e.g. to PR10620, which Eli fixed a few days
  ago), is dropped completely.
- MultiInitializer, which was an ugly hack I added, is dropped again.
- We now have the infrastructure in place to distinguish between
  int x = {1};
  int x({1});
  int x{1};
-- VarDecl now has getInitStyle(), which indicates which of the above was used.
-- CXXConstructExpr now has a flag to indicate that it represents list-
   initialization, although this is not yet used.
- InstantiateInitializer was renamed to SubstInitializer and simplified.
- ActOnParenOrParenListExpr has been replaced by ActOnParenListExpr, which
  always produces a ParenListExpr. Placed that so far failed to convert that
  back to a ParenExpr containing comma operators have been fixed. I'm pretty
  sure I could have made a crashing test case before this.

The end result is a (I hope) considerably cleaner design of initializers.
More importantly, the fact that I can now distinguish between the various
initialization kinds means that I can get the tricky generalized initializer
test cases Johannes Schaub supplied to work. (This is not yet done.)

This commit passed self-host, with the resulting compiler passing the tests. I
hope it doesn't break more complicated code. It's a pretty big change, but one
that I feel is necessary.

llvm-svn: 150318

1 files changed, 8 insertions, 6 deletions

diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index 43aad098178..bd5a1ed3d04 100644
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -1833,14 +1833,16 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
     FieldDecl *NewField = FieldsWithMemberInitializers[I].second;
     Expr *OldInit = OldField->getInClassInitializer();
 
-    SourceLocation LParenLoc, RParenLoc;
-    ASTOwningVector<Expr*> NewArgs(*this);
-    if (InstantiateInitializer(OldInit, TemplateArgs, LParenLoc, NewArgs,
-                               RParenLoc))
+    ExprResult NewInit = SubstInitializer(OldInit, TemplateArgs,
+                                          /*CXXDirectInit=*/false);
+    if (NewInit.isInvalid())
       NewField->setInvalidDecl();
     else {
-      assert(NewArgs.size() == 1 && "wrong number of in-class initializers");
-      ActOnCXXInClassMemberInitializer(NewField, LParenLoc, NewArgs[0]);
+      Expr *Init = NewInit.take();
+      assert(Init && "no-argument initializer in class");
+      assert(!isa<ParenListExpr>(Init) && "call-style init in class");
+      ActOnCXXInClassMemberInitializer(NewField,
+                                       Init->getSourceRange().getBegin(), Init);
     }
   }