Comment 9 for bug 635415

There are specific reasons the patch was done the way it was:

First, it did not make sense to modify in any way the build of plt-scheme on other architectures this close to release. We would have had to rebuild all packages dependent on it, and verify they were not broken as a result of such a change like the one originally proposed to change the linkage and use an external instance of libffi. Hence, I sought a change that only effects and resolves the issue for armel without risking effecting the builds on any other architecture.

Second, because of the way libtool works, it strips out most cflags options when compiling .S files. For this reason, the only clear way to force feed the necessary option from the debian rules was to override CC itself.