[PATCH] Fix compilation errors due to a wrong declaration of iconv() on OS/2

Recent compilers such as GCC 14 generate errors for implicit casts.
---
 configure             |  3 ++-
 osdep/include/iconv.h | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100644 osdep/include/iconv.h

diff --git a/configure b/configure
index 753e14446..e6634bba2 100755
--- a/configure
+++ b/configure
@@ -1961,7 +1961,8 @@ if os2 ; then
   test -n "$ld_static" && ld_static='-Wl,-static'
   # OS/2 linker does not support a thin archive. Remove 'T' flag.
   _arflags=$(echo $_arflags | tr -d T)
-  extra_cflags="$extra_cflags -D_EMX_SOURCE"
+  # -Iosdep/include is for MPlayer, -I../osdep/include is for FFmpeg
+  extra_cflags="$extra_cflags -D_EMX_SOURCE -Iosdep/include -I../osdep/include"
 fi
 
 if wine ; then
diff --git a/osdep/include/iconv.h b/osdep/include/iconv.h
new file mode 100644
index 000000000..daf6d1108
--- /dev/null
+++ b/osdep/include/iconv.h
@@ -0,0 +1,32 @@
+/*
+ * iconv.h for platforms such as OS/2 with non-POSIX compliant iconv.h
+ *
+ * Copyright (c) 2025 KO Myung-Hun ([email protected])
+ *
+ * This file is part of MPlayer.
+ *
+ * MPlayer is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * MPlayer is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with MPlayer; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPLAYER_ICONV_H
+#define MPLAYER_ICONV_H
+
+#define iconv iconv_not_posix
+#include_next <iconv.h>
+
+#undef iconv
+size_t iconv(iconv_t, char **, size_t *, char **, size_t *);
+
+#endif
-- 
2.42.0