Remove ZEND_DVAL_TO_LVAL_CAST_OK (#9215)

* Remove ZEND_DVAL_TO_LVAL_CAST_OK
As far as I can see, this operation should always use the _slow method, and the results seem to be wrong when ZEND_DVAL_TO_LVAL_CAST_OK is enabled.

* update NEWS

Author: zeriyoshi

NEWS

@@ -20,6 +20,7 @@ PHP                                                                        NEWS
 - Standard:
   . Fixed bug GH-9017 (php_stream_sock_open_from_socket could return NULL).
     (Heiko Weber)
+  . Fixed incorrect double to long casting in latest clang. (zeriyoshi)
 
 04 Aug 2022, PHP 8.0.22
 

Zend/Zend.m4

@@ -149,40 +149,6 @@ dnl Checks for library functions.
 AC_CHECK_FUNCS(getpid kill sigsetjmp)
 
 ZEND_CHECK_FLOAT_PRECISION
-
-dnl Test whether double cast to long preserves least significant bits.
-AC_MSG_CHECKING(whether double cast to long preserves least significant bits)
-
-AC_RUN_IFELSE([AC_LANG_SOURCE([[
-#include <limits.h>
-#include <stdlib.h>
-
-int main()
-{
-	if (sizeof(long) == 4) {
-		double d = (double) LONG_MIN * LONG_MIN + 2e9;
-
-		if ((long) d == 2e9 && (long) -d == -2e9) {
-			return 0;
-		}
-	} else if (sizeof(long) == 8) {
-		double correct = 18e18 - ((double) LONG_MIN * -2); /* Subtract ULONG_MAX + 1 */
-
-		if ((long) 18e18 == correct) { /* On 64-bit, only check between LONG_MAX and ULONG_MAX */
-			return 0;
-		}
-	}
-	return 1;
-}
-]])], [
-  AC_DEFINE([ZEND_DVAL_TO_LVAL_CAST_OK], 1, [Define if double cast to long preserves least significant bits])
-  AC_MSG_RESULT(yes)
-], [
-  AC_MSG_RESULT(no)
-], [
-  AC_MSG_RESULT(no)
-])
-
 ])
 
 dnl

Zend/zend_operators.c

@@ -3222,8 +3222,7 @@ ZEND_API const char* ZEND_FASTCALL zend_memnrstr_ex(const char *haystack, const
 }
 /* }}} */
 
-#ifndef ZEND_DVAL_TO_LVAL_CAST_OK
-# if SIZEOF_ZEND_LONG == 4
+#if SIZEOF_ZEND_LONG == 4
 ZEND_API zend_long ZEND_FASTCALL zend_dval_to_lval_slow(double d) /* {{{ */
 {
 	double	two_pow_32 = pow(2., 32.),
@@ -3253,4 +3252,3 @@ ZEND_API zend_long ZEND_FASTCALL zend_dval_to_lval_slow(double d)
 }
 /* }}} */
 #endif
-#endif

Zend/zend_operators.h

@@ -99,16 +99,6 @@ ZEND_API const char* ZEND_FASTCALL zend_memnrstr_ex(const char *haystack, const
 #	define ZEND_DOUBLE_FITS_LONG(d) (!((d) >= (double)ZEND_LONG_MAX || (d) < (double)ZEND_LONG_MIN))
 #endif
 
-#ifdef ZEND_DVAL_TO_LVAL_CAST_OK
-static zend_always_inline zend_long zend_dval_to_lval(double d)
-{
-    if (EXPECTED(zend_finite(d)) && EXPECTED(!zend_isnan(d))) {
-        return (zend_long)d;
-    } else {
-        return 0;
-    }
-}
-#else
 ZEND_API zend_long ZEND_FASTCALL zend_dval_to_lval_slow(double d);
 
 static zend_always_inline zend_long zend_dval_to_lval(double d)
@@ -120,7 +110,6 @@ static zend_always_inline zend_long zend_dval_to_lval(double d)
 	}
 	return (zend_long)d;
 }
-#endif
 
 static zend_always_inline zend_long zend_dval_to_lval_cap(double d)
 {