diff --git a/typo3/install/index.php b/typo3/install/index.php
index d1dee35ebd647c0759297d616baae8ac844dbe1d..34ad236755c5c39b986c0654e8ab1e4e865a507e 100644
--- a/typo3/install/index.php
+++ b/typo3/install/index.php
@@ -1,7 +1,7 @@
 <?php
 
 // Exit early if php requirement is not satisfied.
-if (version_compare(PHP_VERSION, '7.2.0', '<')) {
+if (PHP_VERSION_ID < 70200) {
     die('This version of TYPO3 CMS requires PHP 7.2 or above');
 }
 
diff --git a/typo3/sysext/backend/Resources/Private/Php/backend.php b/typo3/sysext/backend/Resources/Private/Php/backend.php
index 352dbc9512bf39ea9577d71560665a0ead7c160b..737d56ac4cd8b0385b307536e8c53e149a57194e 100644
--- a/typo3/sysext/backend/Resources/Private/Php/backend.php
+++ b/typo3/sysext/backend/Resources/Private/Php/backend.php
@@ -13,7 +13,7 @@
  */
 
 // Exit early if php requirement is not satisfied.
-if (version_compare(PHP_VERSION, '7.2.0', '<')) {
+if (PHP_VERSION_ID < 70200) {
     die('This version of TYPO3 CMS requires PHP 7.2 or above');
 }
 
diff --git a/typo3/sysext/core/Classes/Console/CommandApplication.php b/typo3/sysext/core/Classes/Console/CommandApplication.php
index 6941bd66d7075fa5e10f765d338a3e3968e708d6..36c43e636333ebe07b20470daa1e4109abaf5355 100644
--- a/typo3/sysext/core/Classes/Console/CommandApplication.php
+++ b/typo3/sysext/core/Classes/Console/CommandApplication.php
@@ -57,7 +57,7 @@ class CommandApplication implements ApplicationInterface
      */
     protected function checkEnvironmentOrDie()
     {
-        if (php_sapi_name() !== 'cli') {
+        if (PHP_SAPI !== 'cli') {
             die('Not called from a command line interface (e.g. a shell or scheduler).' . LF);
         }
     }
diff --git a/typo3/sysext/core/Classes/Imaging/GraphicalFunctions.php b/typo3/sysext/core/Classes/Imaging/GraphicalFunctions.php
index 202dcf62f212acab1cda109b3012345e100e7a34..0ca004b835510488e033c2c39b3f0ff43038938c 100644
--- a/typo3/sysext/core/Classes/Imaging/GraphicalFunctions.php
+++ b/typo3/sysext/core/Classes/Imaging/GraphicalFunctions.php
@@ -676,7 +676,7 @@ class GraphicalFunctions
      */
     public function txtPosition($conf, $workArea, $BB)
     {
-        $angle = (int)$conf['angle'] / 180 * pi();
+        $angle = (int)$conf['angle'] / 180 * M_PI;
         $conf['angle'] = 0;
         $straightBB = $this->calcBBox($conf);
         // offset, align, valign, workarea
@@ -1341,11 +1341,11 @@ class GraphicalFunctions
         $res = [];
         if ($distance && $iterations) {
             for ($a = 0; $a < $iterations; $a++) {
-                $yOff = round(sin(2 * pi() / $iterations * ($a + 1)) * 100 * $distance);
+                $yOff = round(sin(2 * M_PI / $iterations * ($a + 1)) * 100 * $distance);
                 if ($yOff) {
                     $yOff = (int)(ceil(abs($yOff / 100)) * ($yOff / abs($yOff)));
                 }
-                $xOff = round(cos(2 * pi() / $iterations * ($a + 1)) * 100 * $distance);
+                $xOff = round(cos(2 * M_PI / $iterations * ($a + 1)) * 100 * $distance);
                 if ($xOff) {
                     $xOff = (int)(ceil(abs($xOff / 100)) * ($xOff / abs($xOff)));
                 }
diff --git a/typo3/sysext/fluid/Tests/Unit/ViewHelpers/Format/NumberViewHelperTest.php b/typo3/sysext/fluid/Tests/Unit/ViewHelpers/Format/NumberViewHelperTest.php
index f5e2a49f0311e8ea8b997c74450693a96a60f451..271390d995fa43839a86bf9c514b5b04a5b94b99 100644
--- a/typo3/sysext/fluid/Tests/Unit/ViewHelpers/Format/NumberViewHelperTest.php
+++ b/typo3/sysext/fluid/Tests/Unit/ViewHelpers/Format/NumberViewHelperTest.php
@@ -34,7 +34,7 @@ class NumberViewHelperTest extends ViewHelperBaseTestcase
         $this->injectDependenciesIntoViewHelper($this->viewHelper);
         $this->viewHelper->setRenderChildrenClosure(
             function () {
-                return pi();
+                return M_PI;
             }
         );
     }
@@ -88,7 +88,7 @@ class NumberViewHelperTest extends ViewHelperBaseTestcase
     public function formatNumberWithThousandsSeparator()
     {
         $this->viewHelper->setRenderChildrenClosure(function () {
-            return pi() * 1000;
+            return M_PI * 1000;
         });
         $this->setArgumentsUnderTest(
             $this->viewHelper,
diff --git a/typo3/sysext/frontend/Resources/Private/Php/frontend.php b/typo3/sysext/frontend/Resources/Private/Php/frontend.php
index 7fddec21d0720c013805c7f68e99137e072408fd..4681a4a5cf399c1e019819bec187f36668469d69 100644
--- a/typo3/sysext/frontend/Resources/Private/Php/frontend.php
+++ b/typo3/sysext/frontend/Resources/Private/Php/frontend.php
@@ -13,7 +13,7 @@
  */
 
 // Exit early if php requirement is not satisfied.
-if (version_compare(PHP_VERSION, '7.2.0', '<')) {
+if (PHP_VERSION_ID < 70200) {
     die('This version of TYPO3 CMS requires PHP 7.2 or above');
 }
 
diff --git a/typo3/sysext/install/Classes/SystemEnvironment/Check.php b/typo3/sysext/install/Classes/SystemEnvironment/Check.php
index 6b63986e125f62b66279f8a33dd5ca986d024f99..407be99918ff55f819953bffe6ae9799f00e4135 100644
--- a/typo3/sysext/install/Classes/SystemEnvironment/Check.php
+++ b/typo3/sysext/install/Classes/SystemEnvironment/Check.php
@@ -250,7 +250,7 @@ class Check implements CheckInterface
     protected function checkPhpVersion()
     {
         $minimumPhpVersion = '7.2.0';
-        $currentPhpVersion = phpversion();
+        $currentPhpVersion = PHP_VERSION;
         if (version_compare($currentPhpVersion, $minimumPhpVersion) < 0) {
             $this->messageQueue->enqueue(new FlashMessage(
                 'Your PHP version ' . $currentPhpVersion . ' is too old. TYPO3 CMS does not run'
diff --git a/typo3/sysext/install/Resources/Private/Php/install.php b/typo3/sysext/install/Resources/Private/Php/install.php
index 7ce212a20a76cfdcdbaf787249b0e4376e9a3d14..b0a70eeab749c76c8057d3488e7e3dfab3ac02cf 100644
--- a/typo3/sysext/install/Resources/Private/Php/install.php
+++ b/typo3/sysext/install/Resources/Private/Php/install.php
@@ -94,7 +94,7 @@
  */
 
 // Exit early if php requirement is not satisfied.
-if (version_compare(PHP_VERSION, '7.2.0', '<')) {
+if (PHP_VERSION_ID < 70200) {
     die('This version of TYPO3 CMS requires PHP 7.2 or above');
 }