無(wú)效字符串計算的通知和警告

New E_WARNING and E_NOTICE errors have been introduced when invalid strings are coerced using operators expecting numbers (+ - * / ** % << >> | & ^) or their assignment equivalents. An E_NOTICE is emitted when the string begins with a numeric value but contains trailing non-numeric characters, and an E_WARNING is emitted when the string does not contain a numeric value.

Notice: A non well formed numeric value encountered in %s on line %d
Warning: A non-numeric value encountered in %s on line %d

八進(jìn)制轉義序列溢出時(shí)發(fā)出警告

Previously, 3-octet octal string escape sequences would overflow silently. Now, they will still overflow, but E_WARNING will be emitted.

Warning: Octal escape sequence overflow \500 is greater than \377 in %s on line %d
string(1) "@"

$this 不一致的修正

Whilst $this is considered a special variable in PHP, it lacked proper checks to ensure it wasn't used as a variable name or reassigned. This has now been rectified to ensure that $this cannot be a user-defined variable, reassigned to a different value, or be globalised.

無(wú)需散列即可生成 Session ID

Session ID 將不再在生成時(shí)進(jìn)行哈希。這一變化，會(huì )導致以下四個(gè) ini 設置不再使用：

• session.entropy_file
• session.entropy_length
• session.hash_function
• session.hash_bits_per_character

并增加以下兩個(gè) ini 設置：

• session.sid_length - 定義會(huì )話(huà) ID 的長(cháng)度（為了向后兼容，默認為 32 個(gè)字符）
• session.sid_bits_per_character - 定義了每個(gè)字符的存儲位數（即增加了會(huì )話(huà) ID 中可使用的字符范圍），為了向后兼容，默認為 4

INI 文件處理的變化

precision

If the value is set to -1, then the dtoa mode 0 is used. The default value is still 14.

serialize_precision

If the value is set to -1, then the dtoa mode 0 is used. The value -1 is now used by default.

gd.jpeg_ignore_warning

The default of this php.ini setting has been changed to 1, so by default libjpeg warnings are ignored.

opcache.enable_cli

The default of this php.ini setting has been changed to 1 (enabled) in PHP 7.1.2, and back to 0 (disabled) in PHP 7.1.7.

Session ID generation with a CSPRNG only

Session IDs will now only be generated with a CSPRNG.

More informative TypeError messages when null is allowed

TypeError exceptions for arg_info type checks will now provide more informative error messages. If the parameter type or return type accepts null (by either having a default value of null or being a nullable type), then the error message will now mention this with a message of "must be ... or null" or "must ... or be null."