Unary minus const expression consistency

- of 0.0 should result in -0.0

Closes GH-10978

Author: iluuu1994

NEWS

@@ -2,6 +2,9 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? ????, PHP 8.1.19
 
+- Core:
+  . Fix inconsistent float negation in constant expressions. (ilutov)
+
 - DOM:
   . Fixed bug #80602 (Segfault when using DOMChildNode::before()).
     (Nathan Freeman)

Zend/tests/unary_minus_const_expr_consistency.phpt

@@ -0,0 +1,16 @@
+--TEST--
+Unary minus constant expression consistency
+--FILE--
+<?php
+
+const ZERO = 0.0;
+const MINUS_ZERO = -ZERO;
+$minus_zero = -ZERO;
+
+var_dump(MINUS_ZERO);
+var_dump($minus_zero);
+
+?>
+--EXPECT--
+float(-0)
+float(-0)

Zend/zend_ast.c

@@ -662,8 +662,8 @@ ZEND_API zend_result ZEND_FASTCALL zend_ast_evaluate(zval *result, zend_ast *ast
 			if (UNEXPECTED(zend_ast_evaluate(&op2, ast->child[0], scope) != SUCCESS)) {
 				ret = FAILURE;
 			} else {
-				ZVAL_LONG(&op1, 0);
-				ret = sub_function(result, &op1, &op2);
+				ZVAL_LONG(&op1, -1);
+				ret = mul_function(result, &op1, &op2);
 				zval_ptr_dtor_nogc(&op2);
 			}
 			break;