From 6da65c6bc1f02096ed1d022d25e5bbb642190acb Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Wed, 8 Jul 2026 13:50:15 -0400
Subject: [PATCH 1/3] .github/actions/apk/action.yml: don't install
 gnu-libiconv-dev

If we do not install GNU libiconv, the musl libc iconv()
implementation should take over, allowing it to be tested
on the CI.
---
 .github/actions/apk/action.yml | 1 -
 1 file changed, 1 deletion(-)

diff --git a/.github/actions/apk/action.yml b/.github/actions/apk/action.yml
index 0cda4963a6a9..8d0fee161187 100644
--- a/.github/actions/apk/action.yml
+++ b/.github/actions/apk/action.yml
@@ -28,7 +28,6 @@ runs:
             curl-dev \
             freetype-dev \
             gettext-dev \
-            gnu-libiconv-dev \
             gmp-dev \
             icu-dev \
             icu-data-full \

From 139eb4c71a082df1b6d82178bce2b5c2c1667895 Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Wed, 8 Jul 2026 13:59:25 -0400
Subject: [PATCH 2/3] .github/actions/configure-alpine/action.yml: drop
 --with-iconv arg

There should be no need to pass /usr as an argument to --with-iconv
now that the system (libc) implementation is being used.
---
 .github/actions/configure-alpine/action.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/actions/configure-alpine/action.yml b/.github/actions/configure-alpine/action.yml
index fe02dacfcdaf..d1b4cfea0412 100644
--- a/.github/actions/configure-alpine/action.yml
+++ b/.github/actions/configure-alpine/action.yml
@@ -43,7 +43,7 @@ runs:
           --enable-pcntl \
           --with-readline \
           --enable-mbstring \
-          --with-iconv=/usr \
+          --with-iconv \
           --with-curl \
           --with-gettext \
           --enable-sockets \

From 659d9779b553d2e4cfb892dbfca7d63b4f85fe9e Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Wed, 1 Jul 2026 22:55:56 -0400
Subject: [PATCH 3/3] ext/iconv/tests/bug48147.phpt: whitelist iconvs with
 //IGNORE

This test is for the behavior of iconv's magic "//IGNORE" suffix. The
output it expects agrees with POSIX 2024 even when the underlying
implementation (glibc) does not. A comment has been added to this
effect, and two calls to urlencode() have been removed so that two
(expected) errors are not swallowed.

Afterwards, we whitelist the two iconv implementations that are known
to support //IGNORE. While POSIX standardizes its behavior, it falls
short of requiring implementations to support it. Musl in particular
does not support any suffix.
---
 ext/iconv/tests/bug48147.phpt | 32 ++++++++++++++++++++++++++++----
 1 file changed, 28 insertions(+), 4 deletions(-)

diff --git a/ext/iconv/tests/bug48147.phpt b/ext/iconv/tests/bug48147.phpt
index ce304eecfb3c..434f71e517bb 100644
--- a/ext/iconv/tests/bug48147.phpt
+++ b/ext/iconv/tests/bug48147.phpt
@@ -2,17 +2,41 @@
 Bug #48147 (iconv with //IGNORE cuts the string)
 --EXTENSIONS--
 iconv
+--SKIPIF--
+<?php
+/*
+ * POSIX 2024 specifies how the "//IGNORE" suffix should behave, but
+ * falls short of requiring implementations to support it (iconv_open
+ * is allowed to return EINVAL for a suffix it does not recognize).
+ *
+ * Many implementations still do not support it, which is OK. We
+ * whitelist the ones that are known to.
+ */
+if (ICONV_IMPL != "glibc" && ICONV_IMPL != "libiconv") {
+    die("skip iconv implementation may not support //IGNORE");
+}
+?>
 --FILE--
 <?php
+/*
+ * POSIX says that when //IGNORE is specified, invalid bytes followed
+ * by valid bytes "shall not be treated as an error." GNU iconv does
+ * not follow this convention, but PHP does the right thing. In the
+ * examples below, invalid bytes in the middle of the string get
+ * dropped, and a string is returned. The two examples where the
+ * problem is at the end do not qualify for the "shall not" exception
+ * because there are no VALID bytes after the error. So PHP is morally
+ * correct in those cases to return an error (false).
+ */
 $text = "aa\xC3\xC3\xC3\xB8aa";
 var_dump(iconv("UTF-8", "UTF-8", $text));
 var_dump(urlencode(iconv("UTF-8", "UTF-8//IGNORE", $text)));
 // only invalid
-var_dump(urlencode(iconv("UTF-8", "UTF-8//IGNORE", "\xC3")));
+var_dump(iconv("UTF-8", "UTF-8//IGNORE", "\xC3"));
 // start invalid
 var_dump(urlencode(iconv("UTF-8", "UTF-8//IGNORE", "\xC3\xC3\xC3\xB8aa")));
 // finish invalid
-var_dump(urlencode(iconv("UTF-8", "UTF-8//IGNORE", "aa\xC3\xC3\xC3")));
+var_dump(iconv("UTF-8", "UTF-8//IGNORE", "aa\xC3\xC3\xC3"));
 ?>
 --EXPECTF--
 Notice: iconv(): Detected an illegal character in input string in %s on line %d
@@ -20,8 +44,8 @@ bool(false)
 string(10) "aa%C3%B8aa"
 
 Notice: iconv(): Detected an incomplete multibyte character in input string in %s on line %d
-string(0) ""
+bool(false)
 string(8) "%C3%B8aa"
 
 Notice: iconv(): Detected an incomplete multibyte character in input string in %s on line %d
-string(0) ""
+bool(false)