------- Comment #2 from oblivian at users dot sourceforge dot net 2008-04-03 20:45 ------- Ok so the gcc/g++ i build has optimization on by default. The configuration scripts don't seem to take this into account and the call to CXX for the atomic check is optimizing away the check in the output assembly code; thus, the grep for __sync_fetch_and_add fails and does not turn off atomic builtins.
the following is right before the code generation in the configure file # Fake what AC_TRY_COMPILE does. XXX Look at redoing this new-style. The check probably needs to also take into account optimization so that the check for __sync_fetch_and_add can not be removed regardless of optimization flags. To revert to 4.2.3 behavior I inserted a -O0 in the ac_compile command for the check. -- oblivian at users dot sourceforge dot net changed: What |Removed |Added ---------------------------------------------------------------------------- Summary|libstdc++ built during |libstdc++ build during |bootstrap is pulling in host|bootstrap is optimizing away |g++ support for atomic |atomic builtin check |builtins | http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35816