to be gcc's default before r198344, calls to atomic builtins will not be
expanded inline. Instead, they will be generated as calls to external
functions (e.g. __sync_fetch_and_add_N), leading to linking errors later
on.
Put in a seatbelt that disables use of atomic builtins in libstdc++ and
llvm, when tuning specifically for the real i386 CPU. This does not
protect against all possible issues, but it is better than nothing.
Because FreeBSD no longer supports the 80386 cpu all code targeting
FreeBSD/i386 necessarily runs on i486 or higher so the compiler
built-ins can be used by default inside libstdc++ and in C++ headers.
This allows newly compiled C++ code to inline some atomic operations.
Old binaries continue to use libstdc++ functions.
PR: 148926
Tested by: Yuri Karaban <tech askold net>
Reviewed by: kan
Approved by: kib (mentor)
MFC after: 2 weeks
Also:
Switch FreeBSD to use libgcc_s.so.1.
Use dl_iterate_phdr to locate shared objects' exception frame
info instead of depending on older register_frame_info machinery.
This allows us to avoid depending on libgcc_s.so.1 in binaries
that do not use exception handling directly. As an additional
benefit it breaks circular libc <=> libgcc_s.so.1 dependency too.
Build newly added libgomp.so.1 library, the runtime support
bits for OpenMP.
Build LGPLed libssp library. Our libc provides our own
BSD-licensed SSP callbacks implementation, so this library
is only built to benefit applications that have hadcoded
knowledge of libssp.so and libssp_nonshared.a. When linked
in from command line, these libraries override libc
implementation.
not to blindly undef isnan() and other functions that became macros in C99.
Enable use of newly grown C99 functions: strtof(), strtold(), wcstof()
Submitted by: das
