diff --git a/resources/functionMap.php b/resources/functionMap.php
index c17a2484d3..7652eedac4 100644
--- a/resources/functionMap.php
+++ b/resources/functionMap.php
@@ -933,7 +933,7 @@
 'CallbackFilterIterator::next' => ['void'],
 'CallbackFilterIterator::rewind' => ['void'],
 'CallbackFilterIterator::valid' => ['bool'],
-'ceil' => ['float|false', 'number'=>'float'],
+'ceil' => ['__benevolent<float|false>', 'number'=>'float'],
 'chdb::__construct' => ['void', 'pathname'=>'string'],
 'chdb::get' => ['string', 'key'=>'string'],
 'chdb_create' => ['bool', 'pathname'=>'string', 'data'=>'array'],
@@ -2991,7 +2991,7 @@
 'finfo_set_flags' => ['bool', 'finfo'=>'resource', 'options'=>'int'],
 'floatval' => ['float', 'var'=>'scalar|array|resource|null'],
 'flock' => ['bool', 'fp'=>'resource', 'operation'=>'int', '&w_wouldblock='=>'int'],
-'floor' => ['float|false', 'number'=>'float'],
+'floor' => ['__benevolent<float|false>', 'number'=>'float'],
 'flush' => ['void'],
 'fmod' => ['float', 'x'=>'float', 'y'=>'float'],
 'fnmatch' => ['bool', 'pattern'=>'string', 'filename'=>'string', 'flags='=>'int'],
@@ -3311,7 +3311,7 @@
 'get_extension_funcs' => ['list<callable-string>|false', 'extension_name'=>'string'],
 'get_headers' => ['array|false', 'url'=>'string', 'format='=>'int', 'context='=>'resource'],
 'get_html_translation_table' => ['array', 'table='=>'int', 'flags='=>'int', 'encoding='=>'string'],
-'get_include_path' => ['string|false'],
+'get_include_path' => ['__benevolent<string|false>'],
 'get_included_files' => ['list<string>'],
 'get_loaded_extensions' => ['list<string>', 'zend_extensions='=>'bool'],
 'get_magic_quotes_gpc' => ['false'],
@@ -6494,8 +6494,8 @@
 'MemcachePool::set' => ['bool', 'key'=>'string', 'var'=>'mixed', 'flag='=>'int', 'expire='=>'int'],
 'MemcachePool::setCompressThreshold' => ['bool', 'threshold'=>'int', 'min_savings='=>'float'],
 'MemcachePool::setServerParams' => ['bool', 'host'=>'string', 'port='=>'int', 'timeout='=>'int', 'retry_interval='=>'int', 'status='=>'bool', 'failure_callback='=>'callable'],
-'memory_get_peak_usage' => ['int', 'real_usage='=>'bool'],
-'memory_get_usage' => ['int', 'real_usage='=>'bool'],
+'memory_get_peak_usage' => ['positive-int', 'real_usage='=>'bool'],
+'memory_get_usage' => ['positive-int', 'real_usage='=>'bool'],
 'MessageFormatter::__construct' => ['void', 'locale'=>'string', 'pattern'=>'string'],
 'MessageFormatter::create' => ['MessageFormatter', 'locale'=>'string', 'pattern'=>'string'],
 'MessageFormatter::format' => ['false|string', 'args'=>'array'],
@@ -6525,7 +6525,7 @@
 'ming_useconstants' => ['void', 'use'=>'int'],
 'ming_useswfversion' => ['void', 'version'=>'int'],
 'mkdir' => ['bool', 'pathname'=>'string', 'mode='=>'int', 'recursive='=>'bool', 'context='=>'resource'],
-'mktime' => ['int|false', 'hour='=>'int', 'min='=>'int', 'sec='=>'int', 'mon='=>'int', 'day='=>'int', 'year='=>'int'],
+'mktime' => ['__benevolent<int|false>', 'hour='=>'int', 'min='=>'int', 'sec='=>'int', 'mon='=>'int', 'day='=>'int', 'year='=>'int'],
 'money_format' => ['string', 'format'=>'string', 'value'=>'float'],
 'Mongo::__construct' => ['void', 'server='=>'string', 'options='=>'array', 'driver_options='=>'array'],
 'Mongo::__get' => ['MongoDB', 'dbname'=>'string'],
@@ -8962,10 +8962,10 @@
 'phdfs::tell' => ['int', 'path'=>'string'],
 'phdfs::write' => ['bool', 'path'=>'string', 'buffer'=>'string', 'mode='=>'string'],
 'php_check_syntax' => ['bool', 'filename'=>'string', 'error_message='=>'string'],
-'php_ini_loaded_file' => ['string|false'],
+'php_ini_loaded_file' => ['non-empty-string|false'],
 'php_ini_scanned_files' => ['string|false'],
 'php_logo_guid' => ['string'],
-'php_sapi_name' => ['string|false'],
+'php_sapi_name' => ['__benevolent<non-empty-string|false>'],
 'php_strip_whitespace' => ['string', 'file_name'=>'string'],
 'php_uname' => ['string', 'mode='=>'string'],
 'php_user_filter::filter' => ['int', 'in'=>'resource', 'out'=>'resource', '&rw_consumed'=>'int', 'closing'=>'bool'],
@@ -10182,7 +10182,7 @@
 'rewind' => ['bool', 'fp'=>'resource'],
 'rewinddir' => ['null|false', 'dir_handle='=>'resource'],
 'rmdir' => ['bool', 'dirname'=>'string', 'context='=>'resource'],
-'round' => ['float|false', 'number'=>'float', 'precision='=>'int', 'mode='=>'1|2|3|4'],
+'round' => ['__benevolent<float|false>', 'number'=>'float', 'precision='=>'int', 'mode='=>'1|2|3|4'],
 'rpm_close' => ['bool', 'rpmr'=>'resource'],
 'rpm_get_tag' => ['mixed', 'rpmr'=>'resource', 'tagnum'=>'int'],
 'rpm_is_valid' => ['bool', 'filename'=>'string'],
diff --git a/resources/functionMap_php80delta.php b/resources/functionMap_php80delta.php
index 4dee6f505e..fbe2debd4b 100644
--- a/resources/functionMap_php80delta.php
+++ b/resources/functionMap_php80delta.php
@@ -28,6 +28,7 @@
 		'bcmod' => ['string', 'dividend'=>'string', 'divisor'=>'string', 'scale='=>'int'],
 		'bcpowmod' => ['string', 'base'=>'string', 'exponent'=>'string', 'modulus'=>'string', 'scale='=>'int'],
 		'call_user_func_array' => ['mixed', 'function'=>'callable', 'parameters'=>'array<int|string,mixed>'],
+		'ceil' => ['float', 'number'=>'float'],
 		'com_load_typelib' => ['bool', 'typelib_name'=>'string', 'case_insensitive='=>'true'],
 		'count_chars' => ['array<int,int>|string', 'input'=>'string', 'mode='=>'int'],
 		'date_add' => ['DateTime', 'object'=>'DateTime', 'interval'=>'DateInterval'],
@@ -43,6 +44,7 @@
 		'date_timezone_set' => ['DateTime', 'object'=>'DateTime', 'timezone'=>'DateTimeZone'],
 		'explode' => ['list<string>', 'separator'=>'non-empty-string', 'str'=>'string', 'limit='=>'int'],
 		'fdiv' => ['float', 'dividend'=>'float', 'divisor'=>'float'],
+		'floor' => ['float', 'number'=>'float'],
 		'forward_static_call_array' => ['mixed', 'function'=>'callable', 'parameters'=>'array<int|string,mixed>'],
 		'get_debug_type' => ['string', 'var'=>'mixed'],
 		'get_resource_id' => ['int', 'res'=>'resource'],
@@ -108,6 +110,7 @@
 		'strrpos' => ['int|false', 'haystack'=>'string', 'needle'=>'string', 'offset='=>'int'],
 		'strstr' => ['string|false', 'haystack'=>'string', 'needle'=>'string', 'before_needle='=>'bool'],
 		'substr' => ['string', 'string'=>'string', 'start'=>'int', 'length='=>'int'],
+		'round' => ['float', 'number'=>'float', 'precision='=>'int', 'mode='=>'1|2|3|4'],
 		'version_compare' => ['int|bool', 'version1'=>'string', 'version2'=>'string', 'operator='=>'string'],
 		'xml_parser_create' => ['XMLParser', 'encoding='=>'string'],
 		'xml_parser_create_ns' => ['XMLParser', 'encoding='=>'string', 'sep='=>'string'],
@@ -162,6 +165,7 @@
 		'bcdiv' => ['?string', 'dividend'=>'string', 'divisor'=>'string', 'scale='=>'int'],
 		'bcmod' => ['?string', 'dividend'=>'string', 'divisor'=>'string', 'scale='=>'int'],
 		'bcpowmod' => ['?string', 'base'=>'string', 'exponent'=>'string', 'modulus'=>'string', 'scale='=>'int'],
+		'ceil' => ['__benevolent<float|false>', 'number'=>'float'],
 		'convert_cyr_string' => ['string', 'str'=>'string', 'from'=>'string', 'to'=>'string'],
 		'com_load_typelib' => ['bool', 'typelib_name'=>'string', 'case_insensitive='=>'bool'],
 		'count_chars' => ['array<int,int>|false|string', 'input'=>'string', 'mode='=>'int'],
@@ -179,6 +183,7 @@
 		'each' => ['array{0:int|string,key:int|string,1:mixed,value:mixed}', '&r_arr'=>'array'],
 		'ezmlm_hash' => ['int', 'addr'=>'string'],
 		'fgetss' => ['string|false', 'fp'=>'resource', 'length='=>'0|positive-int', 'allowable_tags='=>'string'],
+		'floor' => ['__benevolent<float|false>', 'number'=>'float'],
 		'get_magic_quotes_gpc' => ['false'],
 		'gmdate' => ['string|false', 'format'=>'string', 'timestamp='=>'int'],
 		'gmmktime' => ['int|false', 'hour='=>'int', 'minute='=>'int', 'second='=>'int', 'month='=>'int', 'day='=>'int', 'year='=>'int'],
@@ -231,6 +236,7 @@
 		'proc_get_status' => ['array{command: string, pid: int, running: bool, signaled: bool, stopped: bool, exitcode: int, termsig: int, stopsig: int}|false', 'process'=>'resource'],
 		'read_exif_data' => ['array', 'filename'=>'string', 'sections_needed='=>'string', 'sub_arrays='=>'bool', 'read_thumbnail='=>'bool'],
 		'restore_include_path' => ['void'],
+		'round' => ['__benevolent<float|false>', 'number'=>'float', 'precision='=>'int', 'mode='=>'1|2|3|4'],
 		'socket_select' => ['int|false', '&rw_read_fds'=>'resource[]|null', '&rw_write_fds'=>'resource[]|null', '&rw_except_fds'=>'resource[]|null', 'tv_sec'=>'int|null', 'tv_usec='=>'int|null'],
 		'sodium_crypto_aead_chacha20poly1305_ietf_decrypt' => ['?string|?false', 'confidential_message'=>'string', 'public_message'=>'string', 'nonce'=>'string', 'key'=>'string'],
 		'SplFileObject::fgetss' => ['string|false', 'allowable_tags='=>'string'],
diff --git a/src/Type/Php/RoundFunctionReturnTypeExtension.php b/src/Type/Php/RoundFunctionReturnTypeExtension.php
index 839c5c1587..b68471d04c 100644
--- a/src/Type/Php/RoundFunctionReturnTypeExtension.php
+++ b/src/Type/Php/RoundFunctionReturnTypeExtension.php
@@ -6,7 +6,6 @@
 use PHPStan\Analyser\Scope;
 use PHPStan\Php\PhpVersion;
 use PHPStan\Reflection\FunctionReflection;
-use PHPStan\Type\BenevolentUnionType;
 use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
 use PHPStan\Type\FloatType;
@@ -39,21 +38,18 @@ public function isFunctionSupported(FunctionReflection $functionReflection): boo
 		);
 	}
 
-	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): Type
+	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): ?Type
 	{
+		// PHP 7 can return either a float or false.
+		// PHP 8 can either return a float or fatal.
+		$defaultReturnType = null;
+
 		if ($this->phpVersion->hasStricterRoundFunctions()) {
 			// PHP 8 fatals with a missing parameter.
 			$noArgsReturnType = new NeverType(true);
-			// PHP 8 can either return a float or fatal.
-			$defaultReturnType = new FloatType();
 		} else {
 			// PHP 7 returns null with a missing parameter.
 			$noArgsReturnType = new NullType();
-			// PHP 7 can return either a float or false.
-			$defaultReturnType = new BenevolentUnionType([
-				new FloatType(),
-				new ConstantBooleanType(false),
-			]);
 		}
 
 		if (count($functionCall->getArgs()) < 1) {