From 278cc2212b628f3afb342014029cd15fc42aca49 Mon Sep 17 00:00:00 2001
From: Peter Kokot <peterkokot@gmail.com>
Date: Wed, 10 Jul 2024 14:03:54 +0200
Subject: [PATCH 1/3] Fix GH-14443: Cross-compiling with external GD library

This enables cross-compiling simplifications when using external GD
library as requested in GH-14443 using cache variables:

* php_cv_lib_gd_gdImageCreateFromPng
* php_cv_lib_gd_gdImageCreateFromAvif
* php_cv_lib_gd_gdImageCreateFromWebp
* php_cv_lib_gd_gdImageCreateFromJpeg
* php_cv_lib_gd_gdImageCreateFromXpm
* php_cv_lib_gd_gdImageCreateFromBmp
* php_cv_lib_gd_gdImageCreateFromTga

For example:

    ./configure --host=... --build=... --enable-gd --with-external-gd \
        php_cv_lib_gd_gdImageCreateFromPng=yes
---
 NEWS             |  1 +
 ext/gd/config.m4 | 39 ++++++++++++++++++++-------------------
 2 files changed, 21 insertions(+), 19 deletions(-)

diff --git a/NEWS b/NEWS
index db78d1404db09..077c7aa0ce681 100644
--- a/NEWS
+++ b/NEWS
@@ -10,6 +10,7 @@ PHP                                                                        NEWS
     (nielsdos)
   . Fixed OSS-Fuzz #69765. (nielsdos)
   . Fixed bug GH-14741 (Segmentation fault in Zend/zend_types.h). (nielsdos)
+  . Fixed bug GH-14443 (Cross-compiling with external GD library). (Peter Kokot)
 
 - Dom:
   . Fixed bug GH-14702 (DOMDocument::xinclude() crash). (nielsdos)
diff --git a/ext/gd/config.m4 b/ext/gd/config.m4
index 42bb64578ce0a..ad038b697c1d1 100644
--- a/ext/gd/config.m4
+++ b/ext/gd/config.m4
@@ -147,14 +147,15 @@ dnl that gd defines "junk" versions of each gdImageCreateFromFoo function
 dnl even when it does not support the Foo format. Those junk functions
 dnl display a warning but eventually return normally, making a simple link
 dnl or run test insufficient.
-AC_DEFUN([PHP_GD_CHECK_FORMAT],[
-  old_LIBS="${LIBS}"
-  LIBS="${LIBS} ${GD_SHARED_LIBADD}"
-  old_CFLAGS="${CFLAGS}"
-  CFLAGS="${CFLAGS} ${GDLIB_CFLAGS}"
-  AC_MSG_CHECKING([for working gdImageCreateFrom$1 in libgd])
-  AC_LANG_PUSH([C])
-  AC_RUN_IFELSE([AC_LANG_SOURCE([
+AC_DEFUN([PHP_GD_CHECK_FORMAT],
+[AS_VAR_PUSHDEF([php_var], [php_cv_lib_gd_gdImageCreateFrom$1])
+old_LIBS=$LIBS
+LIBS="$LIBS $GD_SHARED_LIBADD"
+old_CFLAGS=$CFLAGS
+CFLAGS="$CFLAGS $GDLIB_CFLAGS"
+AC_LANG_PUSH([C])
+AC_CACHE_CHECK([for working gdImageCreateFrom$1 in libgd], [php_var],
+  [AC_RUN_IFELSE([AC_LANG_SOURCE([
 #include <stdio.h>
 #include <unistd.h>
 #include <gd.h>
@@ -173,17 +174,17 @@ int main(int argc, char** argv) {
   gdSetErrorMethod(exit1);
   gdImagePtr p = gdImageCreateFrom$1(f);
   return 0;
-}])],[
-    AC_MSG_RESULT([yes])
-    AC_DEFINE($2, 1, [Does gdImageCreateFrom$1 work?])
-  ],[
-    AC_MSG_RESULT([no])
-  ],[
-    AC_MSG_RESULT([no])
-  ])
-  AC_LANG_POP([C])
-  CFLAGS="${old_CFLAGS}"
-  LIBS="${old_LIBS}"
+}])],
+  [AS_VAR_SET([php_var], [yes])],
+  [AS_VAR_SET([php_var], [no])],
+  [AS_VAR_SET([php_var], [no])])])
+AS_VAR_IF([php_var], [yes],
+  [AC_DEFINE_UNQUOTED([$2], [1],
+    [Define to 1 if GD library has the 'gdImageCreateFrom$1' function.])])
+AC_LANG_POP([C])
+CFLAGS=$old_CFLAGS
+LIBS=$old_LIBS
+AS_VAR_POPDEF([php_var])
 ])
 
 AC_DEFUN([PHP_GD_CHECK_VERSION],[

From f68a919c4513a58b672288b8bfaca1a3be07e944 Mon Sep 17 00:00:00 2001
From: Peter Kokot <peterkokot@gmail.com>
Date: Wed, 10 Jul 2024 19:17:36 +0200
Subject: [PATCH 2/3] Fix also unused variable and parameter warnings

This also reduces the warnings on more strict compiler settings.
---
 ext/gd/config.m4 | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/ext/gd/config.m4 b/ext/gd/config.m4
index ad038b697c1d1..039b36b961e48 100644
--- a/ext/gd/config.m4
+++ b/ext/gd/config.m4
@@ -162,17 +162,21 @@ AC_CACHE_CHECK([for working gdImageCreateFrom$1 in libgd], [php_var],
 
 /* A custom gdErrorMethod */
 void exit1(int priority, const char *format, va_list args) {
+  (void)priority;
+  (void)format;
+  (void)args;
   _exit(1);
 }
 
 /* Override the default gd_error_method with one that
    actually causes the program to return an error. */
-int main(int argc, char** argv) {
+int main(void) {
   m4_if([$1],[Xpm],
   [char* f = "test.xpm"],
   [FILE* f = NULL]);
   gdSetErrorMethod(exit1);
   gdImagePtr p = gdImageCreateFrom$1(f);
+  (void)p;
   return 0;
 }])],
   [AS_VAR_SET([php_var], [yes])],

From 727329569cf863ea47174a99b9a1d50380974605 Mon Sep 17 00:00:00 2001
From: Peter Kokot <peterkokot@gmail.com>
Date: Wed, 10 Jul 2024 19:27:56 +0200
Subject: [PATCH 3/3] [skip ci] Make CPP macros help texts more sensible to the
 context

---
 ext/gd/config.m4 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ext/gd/config.m4 b/ext/gd/config.m4
index 039b36b961e48..02b571b607764 100644
--- a/ext/gd/config.m4
+++ b/ext/gd/config.m4
@@ -184,7 +184,7 @@ int main(void) {
   [AS_VAR_SET([php_var], [no])])])
 AS_VAR_IF([php_var], [yes],
   [AC_DEFINE_UNQUOTED([$2], [1],
-    [Define to 1 if GD library has the 'gdImageCreateFrom$1' function.])])
+    [Define to 1 if GD library has a working 'gdImageCreateFrom$1' function.])])
 AC_LANG_POP([C])
 CFLAGS=$old_CFLAGS
 LIBS=$old_LIBS