diff --git a/src/Symfony/Component/String/AbstractUnicodeString.php b/src/Symfony/Component/String/AbstractUnicodeString.php
index 9beafe57ebc26..2d29ce91371a7 100644
--- a/src/Symfony/Component/String/AbstractUnicodeString.php
+++ b/src/Symfony/Component/String/AbstractUnicodeString.php
@@ -142,8 +142,10 @@ public function ascii(array $rules = []): self
             } elseif (ICONV_IMPL === 'glibc') {
                 $s = iconv('UTF-8', 'ASCII//TRANSLIT', $s);
             } else {
-                $s = preg_replace_callback('/[^\x00-\x7F]/u', static function ($c) {
-                    $c = iconv('UTF-8', 'ASCII//IGNORE//TRANSLIT', $c[0]);
+                $s = @preg_replace_callback('/[^\x00-\x7F]/u', static function ($c) {
+                    if ('' === $c = (string) iconv('UTF-8', 'ASCII//IGNORE//TRANSLIT', $c[0])) {
+                        throw new \LogicException(sprintf('"%s" requires a translit-able iconv implementation, try installing "gnu-libiconv" if you\'re using Alpine Linux.', static::class));
+                    }
 
                     return 1 < \strlen($c) ? ltrim($c, '\'`"^~') : (\strlen($c) ? $c : '?');
                 }, $s);