diff --git a/src/Type/Constant/ConstantFloatType.php b/src/Type/Constant/ConstantFloatType.php
index eb44693d80..b0cafcdca3 100644
--- a/src/Type/Constant/ConstantFloatType.php
+++ b/src/Type/Constant/ConstantFloatType.php
@@ -49,6 +49,10 @@ private function castFloatToString(float $value): string
 		$precisionBackup = ini_get('precision');
 		ini_set('precision', '-1');
 		try {
+			if (is_nan($value)) {
+				return 'NAN';
+			}
+
 			$valueStr = (string) $value;
 			if (is_finite($value) && !str_contains($valueStr, '.')) {
 				$valueStr .= '.0';