[Bug rtl-optimization/38534] gcc 4.2.1 and above: No need to save called-saved registers in 'noreturn' function

[hjl.tools at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=38534

--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> ---
When I compiled __cxxabiv1::__cxa_throw, which is a noreturn function in
libstdc++-v3/libsupc++/eh_throw.cc not to save callee-saved registers,
most of C++ exception tests crashed.