[Bug libstdc++/51181] [4.7 regression] libstdc++.so __sync_sub_and_fetch_4 linkage error causing many test suite failures on m68k-linux

[joseph at codesourcery dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51181

--- Comment #2 from joseph at codesourcery dot com <joseph at codesourcery dot com> 2011-11-17 21:06:54 UTC ---
FWIW, classic m68k has compare-and-swap, while ColdFire Linux uses kernel 
helpers (available in both vDSO and syscall forms; the syscall forms are 
probably rather easier to use from libgcc than the vDSO is).