codegen: Retain array length for cast from/to generic array

Fixes bug 687728.

diff --git a/codegen/valaccodebasemodule.vala b/codegen/valaccodebasemodule.vala
index 62d1d8a0ab6605e53a4ce95dc6d7495030273890..03f801a75b2cc6d91b5ab00de0959024284bf6ca 100644 (file)
--- a/codegen/valaccodebasemodule.vala
+++ b/codegen/valaccodebasemodule.vala
@@ -5025,14 +5025,21 @@ public abstract class Vala.CCodeBaseModule : CodeGenerator {
                        // recompute array length when casting to other array type
                        var array_type = expr.type_reference as ArrayType;
                        if (array_type != null && expr.inner.value_type is ArrayType) {
-                               var sizeof_to = new CCodeFunctionCall (new CCodeIdentifier ("sizeof"));
-                               sizeof_to.add_argument (new CCodeConstant (get_ccode_name (array_type.element_type)));
+                               if (array_type.element_type is GenericType || ((ArrayType) expr.inner.value_type).element_type is GenericType) {
+                                       // element size unknown for generic arrays, retain array length as is
+                                       for (int dim = 1; dim <= array_type.rank; dim++) {
+                                               append_array_length (expr, get_array_length_cexpression (expr.inner, dim));
+                                       }
+                               } else {
+                                       var sizeof_to = new CCodeFunctionCall (new CCodeIdentifier ("sizeof"));
+                                       sizeof_to.add_argument (new CCodeConstant (get_ccode_name (array_type.element_type)));
 
-                               var sizeof_from = new CCodeFunctionCall (new CCodeIdentifier ("sizeof"));
-                               sizeof_from.add_argument (new CCodeConstant (get_ccode_name (((ArrayType) expr.inner.value_type).element_type)));
+                                       var sizeof_from = new CCodeFunctionCall (new CCodeIdentifier ("sizeof"));
+                                       sizeof_from.add_argument (new CCodeConstant (get_ccode_name (((ArrayType) expr.inner.value_type).element_type)));
 
-                               for (int dim = 1; dim <= array_type.rank; dim++) {
-                                       append_array_length (expr, new CCodeBinaryExpression (CCodeBinaryOperator.DIV, new CCodeBinaryExpression (CCodeBinaryOperator.MUL, get_array_length_cexpression (expr.inner, dim), sizeof_from), sizeof_to));
+                                       for (int dim = 1; dim <= array_type.rank; dim++) {
+                                               append_array_length (expr, new CCodeBinaryExpression (CCodeBinaryOperator.DIV, new CCodeBinaryExpression (CCodeBinaryOperator.MUL, get_array_length_cexpression (expr.inner, dim), sizeof_from), sizeof_to));
+                                       }
                                }
                        } else if (array_type != null) {
                                // cast from non-array to array, set invalid length