Fails to compile with gcc-10 which defaults to -fno-common, cf.:
A possible workaround for this type of bugs is CFLAGS=-fno-common. A patch with proper fix will follow.
Created attachment 657758 [details, diff]
patch fixing the problem
was the patch reported upstream too? If yes, please add a link here.
*** This bug has been marked as a duplicate of bug 709636 ***