[Ffmpeg-devel] OS/X - undefined symbols due to strip'd shared libs

[Steven M. Schultz]

Hi -

	On OS/X the shared libs must be installed with "install -s" which
	strips all the global symbols.  Linking against a stripped library
	gives undefined symbols.

	I noticed this when linking against libavutil.dylib where
	_ff_log2_tab is supposed to reside.  Looking at the symbol table

sms% nm /usr/local/lib/libavutil.dylib

/usr/local/lib/libavutil.dylib(single module):
         U _frexp
         U _ldexp
         U _log

	"install -s" removed _everything_ except the 3 undefineds.

	The attached patch for ./configure creates an 'installstrip' variable
	which can be overriden on a per OS basis.  The default is set to be
	"-s", then in the Darwin) section installstrip="" is done.  Later
	on "INSTALLSTRIP=$installstrip" is used.

	After the patch 'nm /usr/local/lib/libavutil.dylib | grep ff_log2"
	yields:

00002d90 S _ff_log2_tab

	Much better :)

	Cheers,
	Steven Schultz
-------------- next part --------------
--- configure.dist	2005-10-20 21:13:25.000000000 -0700
+++ configure	2005-10-20 22:02:12.000000000 -0700
@@ -229,6 +229,7 @@
 SLIBSUF=".so"
 EXESUF=""
 BUILDSUF=""
+installstrip="-s"
 amr_nb="no"
 amr_wb="no"
 amr_nb_fixed="no"
@@ -333,6 +334,7 @@
 extralibs=""
 darwin="yes"
 strip="strip -x"
+installstrip=""
 LDFLAGS="-Wl,-dynamic,-search_paths_first"
 SLIBSUF=".dylib"
 FFSLDFLAGS=-Wl,-bind_at_load
@@ -1286,7 +1288,7 @@
 echo "RANLIB=$ranlib" >> config.mak
 if test "$dostrip" = "yes" ; then
 echo "STRIP=$strip" >> config.mak
-echo "INSTALLSTRIP=-s" >> config.mak
+echo "INSTALLSTRIP=$installstrip" >> config.mak
 else
 echo "STRIP=echo ignoring strip" >> config.mak
 echo "INSTALLSTRIP=" >> config.mak