diff -r 050939c6181e -r 2b6904506469 jitcraft/Parser.cpp
--- a/jitcraft/Parser.cpp	Wed Jul 04 19:39:00 2012 -0400
+++ b/jitcraft/Parser.cpp	Wed Jul 04 19:54:53 2012 -0400
@@ -1,4 +1,5 @@
-/*
+/* vim: set ts=4 sw=4 tw=99 et:
+ *
  * Copyright (C) 2012 David Anderson
  *
  * This file is part of JITCraft.
@@ -440,10 +441,23 @@
     if (!expect(TOK_RPAREN))
         return NULL;
 
-    Statement *body = localStatement();
+    // Inside a loop, we force the creation of a scope object. Normally, we
+    // will cull scopes if they have no variables. However inside a loop,
+    // function calls that take references may compute a LIFO object, and to
+    // avoid temporarily leaking many such objects, we ensure that a scope
+    // is present so a LIFO slot can be allocated.
+    if (!enterScope(Scope::BLOCK))
+        return NULL;
+
+    Statement *body;
+    if (scanner_.peek() == TOK_LBRACE)
+        body = block(scope_);
+    else
+        body = localStatement();
     if (!body)
         return NULL;
 
+    scope_ = scope_->enclosing();
     return new (pool_) WhileStatement(pos, TOK_WHILE, condition, body);
 }
 
@@ -453,10 +467,20 @@
     SourcePosition pos = scanner_.begin();
     scanner_.scan();
 
-    Statement *body = block();
+    // See the comment in ::while_() as to why we force a scope.
+    if (!enterScope(Scope::BLOCK))
+        return NULL;
+
+    Statement *body;
+    if (scanner_.peek() == TOK_LBRACE)
+        body = block(scope_);
+    else
+        body = localStatement();
     if (!body)
         return NULL;
 
+    scope_ = scope_->enclosing();
+
     if (!expect(TOK_WHILE))
         return NULL;
 
@@ -510,16 +534,26 @@
             return NULL;
     }
 
-    Statement *body = localStatement();
+    // See the comment in ::while_() as to why we force a scope.
+    if (!enterScope(Scope::BLOCK))
+        return NULL;
+
+    Statement *body;
+    if (scanner_.peek() == TOK_LBRACE)
+        body = block(scope_);
+    else
+        body = localStatement();
     if (!body)
         return NULL;
 
-    Scope *blockScope = NULL;
+    scope_ = scope_->enclosing();
+
+    Scope *declScope = NULL;
     if (decl && decl->isVariableDeclaration()) {
-        blockScope = scope_->unlinkIfEmpty();
+        declScope = scope_->unlinkIfEmpty();
         scope_ = scope_->enclosing();
     }
-    return new (pool_) ForStatement(pos, blockScope, decl, condition, update, body);
+    return new (pool_) ForStatement(pos, declScope, decl, condition, update, body);
 }
 
 VariableDeclaration *
@@ -594,13 +628,13 @@
 }
 
 Statement *
-Parser::block()
+Parser::block(Scope *scope)
 {
     if (!expect(TOK_LBRACE))
         return NULL;
 
     SourcePosition pos = scanner_.begin();
-    if (!enterScope(Scope::BLOCK))
+    if (!scope && !enterScope(Scope::BLOCK))
         return NULL;
 
     StatementList *statements = new (pool_) StatementList();
@@ -611,10 +645,11 @@
         statements->append(pool_, statement);
     }
 
-    Scope *blockScope = scope_->unlinkIfEmpty();
-    BlockStatement *block = new (pool_) BlockStatement(pos, blockScope, statements);
-
-    scope_ = scope_->enclosing();
+    if (!scope) {
+    	scope = scope_->unlinkIfEmpty();
+        scope_ = scope_->enclosing();
+    }
+    BlockStatement *block = new (pool_) BlockStatement(pos, scope, statements);
     return block;
 }