File giflib-visibility.patch of Package libgif4

diff -U 3 -H -d -r -N -- a/configure.ac b/configure.ac
--- a/configure.ac	2013-09-03 15:46:48.000000000 +0200
+++ b/configure.ac	2020-05-02 09:31:58.708878104 +0200
@@ -2,15 +2,18 @@
 AC_INIT(giflib, [4.2.3], [esr@thyrsus.com], giflib)
 AC_CONFIG_SRCDIR([lib/dgif_lib.c])
 AM_INIT_AUTOMAKE([gnu dist-bzip2 -Wall])
+AC_CONFIG_MACRO_DIR([m4])
 
 dnl Note: config.h is not used in the current build
 dnl We leave this in place only to supptess an error message at autogen time
 AM_CONFIG_HEADER(config.h)
 
 dnl Checks for programs.
-AC_PROG_LIBTOOL
-AC_PROG_CC
+AC_PROG_CC_STDC
+AC_USE_SYSTEM_EXTENSIONS
+AC_SYS_LARGEFILE
 AC_PROG_CPP
+LT_INIT([pic-only disable-static])
 AC_PROG_INSTALL
 AC_PROG_LN_S
 AC_PROG_MAKE_SET
diff -U 3 -H -d -r -N -- a/lib/gif_hash.h b/lib/gif_hash.h
--- a/lib/gif_hash.h	2013-09-03 15:41:31.000000000 +0200
+++ b/lib/gif_hash.h	2020-05-02 09:39:07.387121449 +0200
@@ -28,6 +28,8 @@
 #define HT_PUT_KEY(l)	(l << 12)
 #define HT_PUT_CODE(l)	(l & 0x0FFF)
 
+#pragma GCC visibility push(hidden)
+
 typedef struct GifHashTableType {
     uint32_t HTable[HT_SIZE];
 } GifHashTableType;
@@ -37,4 +39,6 @@
 void _InsertHashTable(GifHashTableType *HashTable, uint32_t Key, int Code);
 int _ExistsHashTable(GifHashTableType *HashTable, uint32_t Key);
 
+#pragma GCC visibility pop
+
 #endif /* _GIF_HASH_H_ */
diff -U 3 -H -d -r -N -- a/lib/gif_lib_private.h b/lib/gif_lib_private.h
--- a/lib/gif_lib_private.h	2013-09-03 15:41:31.000000000 +0200
+++ b/lib/gif_lib_private.h	2020-05-02 09:40:15.697566860 +0200
@@ -19,6 +19,8 @@
 #define IS_READABLE(Private)    (Private->FileState & FILE_STATE_READ)
 #define IS_WRITEABLE(Private)   (Private->FileState & FILE_STATE_WRITE)
 
+#pragma GCC visibility push(hidden)
+
 typedef struct GifFilePrivateType {
     GifWord FileState, FileHandle,  /* Where all this data goes to! */
       BitsPerPixel,     /* Bits per pixel (Codes uses at least this + 1). */
@@ -46,4 +48,6 @@
 
 extern int _GifError;
 
+#pragma GCC visibility pop
+
 #endif /* _GIF_LIB_PRIVATE_H */
diff -U 3 -H -d -r -N -- a/Makefile.am b/Makefile.am
--- a/Makefile.am	2013-09-03 15:41:31.000000000 +0200
+++ b/Makefile.am	2020-05-02 09:40:56.896629264 +0200
@@ -1,3 +1,4 @@
+ACLOCAL_AMFLAGS = -I m4
 SUBDIRS = lib util doc pic
 
 EXTRA_DIST = Makefile.unx \