wip: more fixes

Author: elsakeirouz

include/swift/Sema/SyntacticElementTarget.h

@@ -41,12 +41,6 @@ struct SequenceIterationInfo {
 
   /// The type of the pattern that matches the elements.
   Type initType;
-
-  /// Implicit `$iterator = <sequence>.makeIterator()`
-  PatternBindingDecl *makeIteratorVar;
-
-  /// Implicit `$iterator.next()` call.
-  Expr *nextCall;
 };
 
 /// Describes information about a for-in loop over a pack that needs to be

lib/Sema/CSGen.cpp

@@ -4664,14 +4664,6 @@ generateForEachStmtConstraints(ConstraintSystem &cs, DeclContext *dc,
   bool isAsync = stmt->getAwaitLoc().isValid();
   auto *sequenceExpr = stmt->getParsedSequence();
 
-  // If we have an unsafe expression for the sequence, lift it out of the
-  // sequence expression. We'll put it back after we've introduced the
-  // various calls.
-  UnsafeExpr *unsafeExpr = dyn_cast<UnsafeExpr>(sequenceExpr);
-  if (unsafeExpr) {
-    sequenceExpr = unsafeExpr->getSubExpr();
-  }
-
   auto contextualLocator = cs.getConstraintLocator(
       sequenceExpr, LocatorPathElt::ContextualType(CTP_ForEachSequence));
   auto elementLocator = cs.getConstraintLocator(

lib/Sema/TypeCheckStmt.cpp

@@ -3465,7 +3465,7 @@ static BraceStmt *desugarForEachStmt(ForEachStmt* stmt){
 
   auto *makeIteratorVar = new (ctx)
       VarDecl(/*isStatic=*/false, VarDecl::Introducer::Var,
-          parsedSequence->getStartLoc(),
+          opaqueSeqExpr->getStartLoc(),
           ctx.getIdentifier(name), dc);
   makeIteratorVar->setImplicit();
 
@@ -3493,7 +3493,9 @@ static BraceStmt *desugarForEachStmt(ForEachStmt* stmt){
   Expr *makeIteratorCall =
         CallExpr::createImplicitEmpty(ctx, makeIteratorRef);
 
-    // Swap in the 'unsafe' expression.
+  // FIXME: commenting this out "fixes" a redundant visit of the sequence's init
+  // expr. We need to investigate this.
+  // Swap in the 'unsafe' expression.
   if (unsafeExpr) {
     unsafeExpr->setSubExpr(makeIteratorCall);
     makeIteratorCall = unsafeExpr;