From 26ba738e33ddd83aeba8c98dc106dd064ea4d7a5 Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Wed, 1 Jul 2026 13:15:50 -0400
Subject: [PATCH] ext/iconv/tests/bug76249.phpt: fallback for non-GNU iconv()

This test fails on musl, where iconv trips over the //IGNORE suffix.
It is not obvious that //IGNORE is required to trigger the issue in
the first place, but since we are ensuring that a security bug is
fixed, it is better to include it where possible.

This commit updates the test to append //IGNORE only on the two GNU
iconv implementations. Others may support it eventually, but at the
moment, despite being part of POSIX, support is inconsistent (as
evidenced by musl, if nothing else). In any case, we still test that
iconv works with an invalid stream.
---
 ext/iconv/tests/bug76249.phpt | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/ext/iconv/tests/bug76249.phpt b/ext/iconv/tests/bug76249.phpt
index 37608ccc0447..b817a3f8285a 100644
--- a/ext/iconv/tests/bug76249.phpt
+++ b/ext/iconv/tests/bug76249.phpt
@@ -4,16 +4,30 @@ Bug #76249 (stream filter convert.iconv leads to infinite loop on invalid sequen
 iconv
 --FILE--
 <?php
+$ignore = "";
+if (ICONV_IMPL == "libiconv" || ICONV_IMPL == "glibc") {
+    // The original bug report used "//IGNORE", and the bug itself
+    // involves the return value and errno from iconv(), so in the
+    // interest of fidelity we include the suffix on systems like the
+    // one where the bug was reported. On other systems however,
+    // despite being mentioned in POSIX 2024, the "//IGNORE" suffix is
+    // not supported consistently. Musl in particular does not support
+    // it at all, so we must omit it to avoid triggering other
+    // (unexpected) errors. In any case, it is nice to check that
+    // iconv and invalid streams do not interact badly.
+    $ignore = "//IGNORE";
+}
+
 $fh = fopen('php://memory', 'rw');
 fwrite($fh, "abc");
 rewind($fh);
-if (false === @stream_filter_append($fh, 'convert.iconv.ucs-2/utf8//IGNORE', STREAM_FILTER_READ, [])) {
-    stream_filter_append($fh, 'convert.iconv.ucs-2/utf-8//IGNORE', STREAM_FILTER_READ, []);
+if (false === @stream_filter_append($fh, "convert.iconv.ucs-2/utf8{$ignore}", STREAM_FILTER_READ, [])) {
+    stream_filter_append($fh, "convert.iconv.ucs-2/utf-8{$ignore}", STREAM_FILTER_READ, []);
 }
 var_dump(stream_get_contents($fh));
 ?>
 DONE
---EXPECTF--
-Warning: stream_get_contents(): iconv stream filter ("ucs-2"=>"utf%A8//IGNORE"): invalid multibyte sequence in %sbug76249.php on line %d
-string(0) ""
+--EXPECTREGEX--
+Warning: stream_get_contents\(\): iconv stream filter \("ucs-2"=>"utf-?8(\/\/IGNORE)?"\): invalid multibyte sequence in .*bug76249\.php on line \d+
+string\(0\) ""
 DONE