I have found an issue while generating swc file using compc command. When I apply this workaround mentioned in http://forums.adobe.com/thread/428576?tstart=0 it generates the swc file, but catalog.xml file (file inside swc file) is very big and contains many entries of flex4 classes. I think that this is not the right behaviour so I have created a bug https://bugs.adobe.com/jira/browse/SDK-21053 and my workaround is to give the location of swc's in the external-library-path argument of compc. I have attached a sample library project which shows the issue, (Note: you may need to edit the build file to give location to your flex sdk). I am currently on revision number 6409. Is this the right approach or I am missing something
I got the answer on the prerelease forum, unfortunately my bug has been closed It could be a update request. Actually by default all framework classes are marked as "Merge into code", so my catalog gets larger while when I mark them as " External Libraries", my swc size is significantly very small.
You don't need the workaround anymore if you use the latest nighly build. The issue was fixed recently in trunk and is not available in the beta build.
Link to the latest nightly build http://opensource.adobe.com/wiki/display/flexsdk/download?build=220.127.116.1130&pkgtype=1
Flex SDK Team