[SCM] libav/experimental: Create shared libraries using versioned filenames and add -rpath-link to LDFLAGS so linker finds them when using --as-needed (which is default in some installations). Using --as-needed is generally a good thing, so add that explicitly as well.

[siretart at users.alioth.debian.org]

The following commit has been merged in the experimental branch:
commit baa3a937815c8bcd47b84cd4a3b450705197b27a
Author: Måns Rullgård <mans at mansr.com>
Date:   Thu May 11 20:36:00 2006 +0000

    Create shared libraries using versioned filenames and add -rpath-link
    to LDFLAGS so linker finds them when using --as-needed (which is default
    in some installations).  Using --as-needed is generally a good thing, so
    add that explicitly as well.
    
    Originally committed as revision 5362 to svn://svn.ffmpeg.org/ffmpeg/trunk

diff --git a/common.mak b/common.mak
index 24ccaed..94272c5 100644
--- a/common.mak
+++ b/common.mak
@@ -31,7 +31,10 @@ $(LIB): $(STATIC_OBJS)
 	$(AR) rc $@ $^ $(EXTRAOBJS)
 	$(RANLIB) $@
 
-$(SLIBNAME): $(SHARED_OBJS)
+$(SLIBNAME): $(SLIBNAME_WITH_MAJOR)
+	ln -sf $^ $@
+
+$(SLIBNAME_WITH_MAJOR): $(SHARED_OBJS)
 	$(CC) $(SHFLAGS) $(LDFLAGS) -o $@ $^ $(EXTRALIBS) $(EXTRAOBJS)
 ifeq ($(CONFIG_WIN32),yes)
 	-lib /machine:i386 /def:$(@:.dll=.def)
diff --git a/configure b/configure
index 4ff62c7..f2b8bac 100755
--- a/configure
+++ b/configure
@@ -228,7 +228,7 @@ vhook="default"
 dlfcn="no"
 dlopen="no"
 mpegaudio_hp="yes"
-SHFLAGS='-shared -Wl,-soname,$@.$(LIBMAJOR)'
+SHFLAGS='-shared -Wl,-soname,$@'
 netserver="no"
 need_inet_aton="no"
 protocols="yes"
@@ -383,7 +383,7 @@ cygwin="yes"
 EXESUF=".exe"
 ;;
 Linux)
-LDFLAGS="$LDFLAGS -rdynamic"
+LDFLAGS="$LDFLAGS -rdynamic -Wl,--as-needed -Wl,-rpath-link,\$(BUILD_ROOT)/libavcodec -Wl,-rpath-link,\$(BUILD_ROOT)/libavformat -Wl,-rpath-link,\$(BUILD_ROOT)/libavutil"
 ;;
 IRIX*)
 ranlib="echo ignoring ranlib"

-- 
Libav/FFmpeg packaging