diff --git a/src/CompilerBase.php b/src/CompilerBase.php
index db84d361..def34fc0 100644
--- a/src/CompilerBase.php
+++ b/src/CompilerBase.php
@@ -3472,7 +3472,14 @@ protected function detectTypeOfExpr($expr): string
                 return Type::BOOL;
             case 'Expr_BitwiseNot':
                 $inner = $this->detectTypeOfExpr($expr->expr);
-                return $inner === Type::BIGINT ? Type::BIGINT : Type::INT;
+                return match ($inner) {
+                    Type::BIGINT => Type::BIGINT,
+                    // ~"abc" inverts the bytes of the string.
+                    Type::STR => Type::STR,
+                    // ~bool and ~array throw a TypeError at runtime.
+                    Type::BOOL, Type::ARRAY => Type::VAR,
+                    default => Type::INT,
+                };
             case 'Expr_Print':
             case 'Expr_Cast_Int':
                 return Type::INT;
diff --git a/src/Parser/UnaryExpressionTrait.php b/src/Parser/UnaryExpressionTrait.php
old mode 100644
new mode 100755
index 07e6a1ef..a38043ae
--- a/src/Parser/UnaryExpressionTrait.php
+++ b/src/Parser/UnaryExpressionTrait.php
@@ -85,6 +85,15 @@ protected function parseBitwiseNot(Expr\BitwiseNot $expr): string
             return 'php::BigInt::bitNot(' . $this->parseExpr($expr->expr) . ')';
         }
         $var = $this->parseIdentifier($expr->expr);
+        // A statically non-numeric operand goes through Zend's
+        // bitwise_not_function(): a string has its bytes inverted and stays a
+        // string, while bool and array raise "Cannot perform bitwise not on ...".
+        if ($type === Type::STR) {
+            return $this->convertStringExpr('(~php::Variant(' . $var . '))');
+        }
+        if ($type === Type::BOOL || $type === Type::ARRAY) {
+            return '(~php::Variant(' . $var . '))';
+        }
         return '~' . $this->convertIntExpr($var);
     }
 
diff --git a/tests/compiler/operator/bitwise-not-operands.phpt b/tests/compiler/operator/bitwise-not-operands.phpt
new file mode 100644
index 00000000..52bb9003
--- /dev/null
+++ b/tests/compiler/operator/bitwise-not-operands.phpt
@@ -0,0 +1,52 @@
+--TEST--
+~ inverts the bytes of a string and raises TypeError for bool, as in PHP
+--FILE--
+<?php
+declare(strict_types=1);
+
+function notb(bool $a): mixed { return ~$a; }
+function nots(string $s): mixed { return ~$s; }
+function notsLocal(string $s): string { $x = ~$s; return $x; }
+function noti(int $i): mixed { return ~$i; }
+function notf(float $f): mixed { return ~$f; }
+function notm(mixed $m): mixed { return ~$m; }
+function twice(string $s): mixed { return ~~$s; }
+
+function t(string $nome, callable $f): void
+{
+    try {
+        $v = $f();
+        echo $nome, ' => ', is_string($v) ? 'string:' . bin2hex($v) : var_export($v, true), "\n";
+    } catch (\Throwable $e) {
+        echo $nome, ' => ', get_class($e), ': ', $e->getMessage(), "\n";
+    }
+}
+
+function main(): void
+{
+    ini_set('display_errors', '0');
+    t('~false', fn() => notb(false));
+    t('~true', fn() => notb(true));
+    t('~"abc"', fn() => nots('abc'));
+    t('~""', fn() => nots(''));
+    t('~"1e3"', fn() => nots('1e3'));
+    t('$x = ~"ab"', fn() => notsLocal('ab'));
+    t('~~"xyz"', fn() => twice('xyz'));
+    t('~5', fn() => noti(5));
+    t('~PHP_INT_MIN', fn() => noti(PHP_INT_MIN));
+    t('~1.5', fn() => notf(1.5));
+    t('~mixed int', fn() => notm(7));
+}
+?>
+--EXPECT--
+~false => TypeError: Cannot perform bitwise not on false
+~true => TypeError: Cannot perform bitwise not on true
+~"abc" => string:9e9d9c
+~"" => string:
+~"1e3" => string:ce9acc
+$x = ~"ab" => string:9e9d
+~~"xyz" => string:78797a
+~5 => -6
+~PHP_INT_MIN => 9223372036854775807
+~1.5 => -2
+~mixed int => -8