1 files changed, 72 insertions, 0 deletions
diff --git a/dev-lang/php/files/php-8.1.27-implicit-decls.patch b/dev-lang/php/files/php-8.1.27-implicit-decls.patch
new file mode 100644
index 000000000000..443b02ba17c2
--- /dev/null
+++ b/dev-lang/php/files/php-8.1.27-implicit-decls.patch
@@ -0,0 +1,72 @@
+From 79df2b9dcbe0388667c832b2c702ca3158330ed7 Mon Sep 17 00:00:00 2001
+From: Michael Orlitzky <michael@orlitzky.com>
+Date: Mon, 4 Mar 2024 11:48:01 -0500
+Subject: [PATCH] ext/iconv/config.m4: add missing stdio.h include.
+
+The next generation of C compilers is going to enforce the C standard
+more strictly:
+
+  https://wiki.gentoo.org/wiki/Modern_C_porting
+
+One warning that will eventually become an error is
+-Wimplicit-function-declaration. This is relatively easy to catch in
+most code (it will fail to compile), but inside of autoconf tests it
+can go unnoticed because many feature-test compilations fail by
+design. For example,
+
+  AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <iconv.h>]],
+                 [[iconv_ccs_init(NULL, NULL);]])]...
+
+is designed to fail if iconv_ccs_init() is not in iconv.h. On the
+other hand,
+
+  AC_RUN_IFELSE([AC_LANG_SOURCE([[
+  #include <iconv.h>
+  int main() {
+    printf("%d", _libiconv_version);
+    return 0;
+  }
+
+should pass if _libiconv_version is defined. If the user has
+-Werror=implicit-function-declaration in his CFLAGS, however,
+it will not:
+
+  $ export CFLAGS="$CFLAGS -Werror=implicit-function-declaration"
+  $ ./configure
+  ...
+  checking if using GNU libiconv... no
+
+This is because the stdio.h header that defines printf() is missing:
+
+  conftest.c:240:3: error: implicit declaration of function 'printf'
+  [-Werror=implicit-function-declaration]
+    240 |   printf("%d", _libiconv_version);
+        |   ^~~~~~
+  conftest.c:239:1: note: include '<stdio.h>' or provide a declaration
+  of 'printf'
+
+This commit adds the include, correcting the test with any compiler
+that balks at implicit function definitions.
+
+(Backport to php-8.1.27)
+
+Closes GH-10751
+---
+ ext/iconv/config.m4 | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/ext/iconv/config.m4 b/ext/iconv/config.m4
+index ac57c81e..b8044bf2 100644
+--- a/ext/iconv/config.m4
++++ b/ext/iconv/config.m4
+@@ -30,6 +30,7 @@ if test "$PHP_ICONV" != "no"; then
+       AC_MSG_CHECKING([if using GNU libiconv])
+       AC_RUN_IFELSE([AC_LANG_SOURCE([[
+ #include <iconv.h>
++#include <stdio.h>
+ int main() {
+   printf("%d", _libiconv_version);
+   return 0;
+-- 
+2.43.0
+