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diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
index c3c35eb..b1feb7a 100644
--- a/Zend/zend_compile.c
+++ b/Zend/zend_compile.c
@@ -6089,7 +6089,19 @@ void zend_do_isset_or_isempty(int type, znode *result, znode *variable TSRMLS_DC

        zend_do_end_variable_parse(variable, BP_VAR_IS, 0 TSRMLS_CC);

-       zend_check_writable_variable(variable);
+       if (type == ZEND_ISEMPTY) {
+               // if the empty() argument is the result of a function call we already
+               // know that the variable exists, so we can just convert the empty()
+               // call to a boolean not
+               if (zend_is_function_or_method_call(variable)) {
+                       zend_do_unary_op(ZEND_BOOL_NOT, result, variable TSRMLS_CC);
+                       return;
+               }
+       } else {
+               // it doesn't make sense to pass the result of a function call to
+               // isset() as it will always be bool(true). Thus disallow them here
+               zend_check_writable_variable(variable);
+       }

        if (variable->op_type == IS_CV) {
                last_op = get_next_op(CG(active_op_array) TSRMLS_CC);
diff --git a/Zend/zend_language_parser.y b/Zend/zend_language_parser.y
index d0730b7..1a9d212 100644
--- a/Zend/zend_language_parser.y
+++ b/Zend/zend_language_parser.y
@@ -1149,6 +1149,7 @@ encaps_var_offset:
 internal_functions_in_yacc:
                T_ISSET '(' isset_variables ')' { $$ = $3; }
        |       T_EMPTY '(' variable ')'        { zend_do_isset_or_isempty(ZEND_ISEMPTY, &$$, &$3 TSRMLS_CC); }
+       |       T_EMPTY '(' expr_without_variable ')' { zend_do_unary_op(ZEND_BOOL_NOT, &$$, &$3 TSRMLS_CC); }
        |       T_INCLUDE expr                  { zend_do_include_or_eval(ZEND_INCLUDE, &$$, &$2 TSRMLS_CC); }
        |       T_INCLUDE_ONCE expr     { zend_do_include_or_eval(ZEND_INCLUDE_ONCE, &$$, &$2 TSRMLS_CC); }
        |       T_EVAL '(' expr ')'     { zend_do_include_or_eval(ZEND_EVAL, &$$, &$3 TSRMLS_CC); }