+
+/* Perform the default conversion of arrays and functions to pointers.
+ Return the result of converting EXP. For any other expression, just
+ return EXP. */
+
+static tree
+default_function_array_conversion (exp)
+ tree exp;
+{
+ tree orig_exp;
+ tree type = TREE_TYPE (exp);
+ enum tree_code code = TREE_CODE (type);
+ int not_lvalue = 0;
+
+ /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
+ an lvalue.
+
+ Do not use STRIP_NOPS here! It will remove conversions from pointer
+ to integer and cause infinite recursion. */
+ orig_exp = exp;
+ while (TREE_CODE (exp) == NON_LVALUE_EXPR
+ || (TREE_CODE (exp) == NOP_EXPR
+ && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
+ {
+ if (TREE_CODE (exp) == NON_LVALUE_EXPR)
+ not_lvalue = 1;
+ exp = TREE_OPERAND (exp, 0);
+ }
+
+ /* Preserve the original expression code. */
+ if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (exp))))
+ C_SET_EXP_ORIGINAL_CODE (exp, C_EXP_ORIGINAL_CODE (orig_exp));
+
+ if (code == FUNCTION_TYPE)
+ {
+ return build_unary_op (ADDR_EXPR, exp, 0);
+ }
+ if (code == ARRAY_TYPE)
+ {
+ tree adr;
+ tree restype = TREE_TYPE (type);
+ tree ptrtype;
+ int constp = 0;
+ int volatilep = 0;
+ int lvalue_array_p;
+
+ if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r' || DECL_P (exp))
+ {
+ constp = TREE_READONLY (exp);
+ volatilep = TREE_THIS_VOLATILE (exp);
+ }
+
+ if (TYPE_QUALS (type) || constp || volatilep)
+ restype
+ = c_build_qualified_type (restype,
+ TYPE_QUALS (type)
+ | (constp * TYPE_QUAL_CONST)
+ | (volatilep * TYPE_QUAL_VOLATILE));
+
+ if (TREE_CODE (exp) == INDIRECT_REF)
+ return convert (TYPE_POINTER_TO (restype),
+ TREE_OPERAND (exp, 0));
+
+ if (TREE_CODE (exp) == COMPOUND_EXPR)
+ {
+ tree op1 = default_conversion (TREE_OPERAND (exp, 1));
+ return build (COMPOUND_EXPR, TREE_TYPE (op1),
+ TREE_OPERAND (exp, 0), op1);
+ }
+
+ lvalue_array_p = !not_lvalue && lvalue_p (exp);
+ if (!flag_isoc99 && !lvalue_array_p
+ && !(TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
+ {
+ /* Before C99, non-lvalue arrays do not decay to pointers.
+ Normally, using such an array would be invalid; but it can
+ be used correctly inside sizeof or as a statement expression.
+ Thus, do not give an error here; an error will result later. */
+ return exp;
+ }
+
+ ptrtype = build_pointer_type (restype);
+
+ if (TREE_CODE (exp) == VAR_DECL)
+ {
+ /* ??? This is not really quite correct
+ in that the type of the operand of ADDR_EXPR
+ is not the target type of the type of the ADDR_EXPR itself.
+ Question is, can this lossage be avoided? */
+ adr = build1 (ADDR_EXPR, ptrtype, exp);
+ if (mark_addressable (exp) == 0)
+ return error_mark_node;
+ TREE_CONSTANT (adr) = staticp (exp);
+ TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
+ return adr;
+ }
+ /* This way is better for a COMPONENT_REF since it can
+ simplify the offset for a component. */
+ adr = build_unary_op (ADDR_EXPR, exp, 1);
+ return convert (ptrtype, adr);
+ }
+ return exp;
+}
+
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