diff --git a/tools/binpac/lib/binpac_exception.h b/tools/binpac/lib/binpac_exception.h
index 328f8c696d..4a4ae40e31 100644
--- a/tools/binpac/lib/binpac_exception.h
+++ b/tools/binpac/lib/binpac_exception.h
@@ -22,12 +22,12 @@ protected:
 	string msg_;
 };
 
-class ExceptionCheckViolation : public Exception
+class ExceptionEnforceViolation : public Exception
 {
 public:
-	ExceptionCheckViolation(const char* where)
+	ExceptionEnforceViolation(const char* where)
 		{
-		append(binpac_fmt("check violation : %s", where));
+		append(binpac_fmt("&enforce violation : %s", where));
 		}
 };
 
diff --git a/tools/binpac/src/pac_attr.h b/tools/binpac/src/pac_attr.h
index 67bdbedc8d..85d7f19afb 100644
--- a/tools/binpac/src/pac_attr.h
+++ b/tools/binpac/src/pac_attr.h
@@ -8,6 +8,7 @@ enum AttrType {
 	ATTR_BYTEORDER, 
 	ATTR_CHECK, 
 	ATTR_CHUNKED,
+	ATTR_ENFORCE,
 	ATTR_EXPORTSOURCEDATA,
 	ATTR_IF,
 	ATTR_LENGTH, 
diff --git a/tools/binpac/src/pac_parse.yy b/tools/binpac/src/pac_parse.yy
index 5bf3c96434..178af0604e 100644
--- a/tools/binpac/src/pac_parse.yy
+++ b/tools/binpac/src/pac_parse.yy
@@ -9,7 +9,7 @@
 %token TOK_ID TOK_NUMBER TOK_REGEX TOK_STRING
 %token TOK_BEGIN_RE TOK_END_RE
 %token TOK_ATTR_ALSO
-%token TOK_ATTR_BYTEORDER TOK_ATTR_CHECK TOK_ATTR_CHUNKED 
+%token TOK_ATTR_BYTEORDER TOK_ATTR_CHECK TOK_ATTR_CHUNKED TOK_ATTR_ENFORCE
 %token TOK_ATTR_EXPORTSOURCEDATA TOK_ATTR_IF
 %token TOK_ATTR_LENGTH TOK_ATTR_LET 
 %token TOK_ATTR_LINEBREAKER TOK_ATTR_MULTILINE TOK_ATTR_ONELINE
@@ -994,6 +994,10 @@ attr		:	TOK_ATTR_BYTEORDER '=' expr
 				{
 				$$ = new Attr(ATTR_CHUNKED);
 				}
+		|	TOK_ATTR_ENFORCE expr
+				{
+				$$ = new Attr(ATTR_ENFORCE, $2);
+				}
 		|	TOK_ATTR_EXPORTSOURCEDATA
 				{
 				$$ = new Attr(ATTR_EXPORTSOURCEDATA);
diff --git a/tools/binpac/src/pac_scan.ll b/tools/binpac/src/pac_scan.ll
index 0324ef0aa8..f5dab77c64 100644
--- a/tools/binpac/src/pac_scan.ll
+++ b/tools/binpac/src/pac_scan.ll
@@ -184,6 +184,7 @@ ESCSEQ	(\\([^\n]|[0-7]{3}|x[[:xdigit:]]{2}))
 <INITIAL>&byteorder		return TOK_ATTR_BYTEORDER;
 <INITIAL>&check			return TOK_ATTR_CHECK;
 <INITIAL>&chunked		return TOK_ATTR_CHUNKED;
+<INITIAL>&enforce			return TOK_ATTR_ENFORCE;
 <INITIAL>&exportsourcedata	return TOK_ATTR_EXPORTSOURCEDATA;
 <INITIAL>&if			return TOK_ATTR_IF;
 <INITIAL>&length		return TOK_ATTR_LENGTH;
diff --git a/tools/binpac/src/pac_type.cc b/tools/binpac/src/pac_type.cc
index 5f06b2b760..044a5305d1 100644
--- a/tools/binpac/src/pac_type.cc
+++ b/tools/binpac/src/pac_type.cc
@@ -52,6 +52,7 @@ Type::Type(TypeType tot)
 	attrs_ = new AttrList();
 	attr_byteorder_expr_ = 0;
 	attr_checks_ = new ExprList();
+	attr_enforces_ = new ExprList();
 	attr_chunked_ = false;
 	attr_exportsourcedata_ = false;
 	attr_if_expr_ = 0;
@@ -81,6 +82,7 @@ Type::~Type()
 	delete attr_if_expr_;
 	delete attr_length_expr_;
 	delete_list(ExprList, attr_checks_);
+	delete_list(ExprList, attr_enforces_);
 	delete_list(ExprList, attr_requires_);
 	}
 
@@ -159,6 +161,10 @@ void Type::ProcessAttr(Attr* a)
 			attr_checks_->push_back(a->expr());
 			break;
 
+		case ATTR_ENFORCE:
+			attr_enforces_->push_back(a->expr());
+			break;
+
 		case ATTR_EXPORTSOURCEDATA:
 			attr_exportsourcedata_ = true;
 			break;
@@ -785,15 +791,15 @@ void Type::GenParseCode3(Output* out_cc, Env* env, const DataPtr& data, int flag
 	if ( size_var() )
 		ASSERT(env->Evaluated(size_var()));
 
-	foreach(i, ExprList, attr_checks_)
+	foreach(i, ExprList, attr_enforces_)
 		{
-		Expr* check = *i;
-		const char* check_expr = check->EvalExpr(out_cc, env);
-		out_cc->println("// Evaluate '&check' attribute");
-		out_cc->println("if (!%s)", check_expr);
+		Expr* enforce = *i;
+		const char* enforce_expr = enforce->EvalExpr(out_cc, env);
+		out_cc->println("// Evaluate '&enforce' attribute");
+		out_cc->println("if (!%s)", enforce_expr);
 		out_cc->inc_indent();
 		out_cc->println("{");
-		out_cc->println("throw binpac::ExceptionCheckViolation(\"%s\");", data_id_str_.c_str());
+		out_cc->println("throw binpac::ExceptionEnforceViolation(\"%s\");", data_id_str_.c_str());
 		out_cc->println("}");
 		out_cc->dec_indent();
 		}
diff --git a/tools/binpac/src/pac_type.h b/tools/binpac/src/pac_type.h
index 6590a94a5a..2de0a6fc76 100644
--- a/tools/binpac/src/pac_type.h
+++ b/tools/binpac/src/pac_type.h
@@ -284,6 +284,7 @@ protected:
 
 	Expr *attr_byteorder_expr_;
 	ExprList *attr_checks_;
+	ExprList *attr_enforces_;
 	bool attr_chunked_;
 	bool attr_exportsourcedata_;
 	Expr *attr_if_expr_;