diff --git a/client-php/tests/ProcessTest.php b/client-php/tests/ProcessTest.php
index 3819b8c..b3c1f77 100644
--- a/client-php/tests/ProcessTest.php
+++ b/client-php/tests/ProcessTest.php
@@ -38,7 +38,7 @@ public function testWarningAndUncaughtException(): void
     {
         [$exitCode, $output, $events] = $this->runScript('errors.php');
 
-        self::assertSame(255, $exitCode);
+        self::assertSame(255, $exitCode, $output);
         self::assertStringContainsString('Order 7 not found', $output, 'PHP still reports the uncaught exception');
         self::assertStringContainsString('Undefined index: discount', $output, 'and the warning');
         self::assertSame(['request_start', 'message', 'error', 'error', 'request_end'], array_column($events, 'type'));
@@ -51,9 +51,13 @@ public function testWarningAndUncaughtException(): void
 
     public function testFatalError(): void
     {
+        if (!self::phpRunsShutdownAfterOutOfMemory()) {
+            self::markTestSkipped('This PHP build exits with code 1 on running out of memory and skips shutdown functions, '
+                . 'without the library too (seen in setup-php builds of PHP 7.4-8.1 from October 2026)');
+        }
         [$exitCode, $output, $events] = $this->runScript('fatal.php');
 
-        self::assertSame(255, $exitCode);
+        self::assertSame(255, $exitCode, $output);
         self::assertStringContainsString('Allowed memory size', $output);
         self::assertSame(['request_start', 'error', 'request_end'], array_column($events, 'type'));
         self::assertSame('fatal', $events[1]['kind']);
@@ -61,6 +65,17 @@ public function testFatalError(): void
         self::assertSame(255, $events[2]['exit_code']);
     }
 
+    /** Whether bare PHP, with no extensions and no library, still runs shutdown functions after running out of memory. */
+    private static function phpRunsShutdownAfterOutOfMemory(): bool
+    {
+        $code = 'register_shutdown_function(function () { echo "shutdown"; }); '
+            . 'while (true) { $chunks[] = str_repeat("x", 1024 * 1024); }';
+        $command = sprintf('%s -n -d memory_limit=16M -d display_errors=0 -r %s 2>&1', escapeshellarg(PHP_BINARY), escapeshellarg($code));
+        exec($command, $output, $exitCode);
+
+        return $exitCode === 255 && implode("\n", $output) === 'shutdown';
+    }
+
     public function testProjectOfLibraryV1WithoutComposer(): void
     {
         [$exitCode, $output, $events] = $this->runScript('compat.php', [