[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 #22 from H.J. Lu <hjl.tools at gmail dot com> ---
Created attachment 57243
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57243&action=edit
A patch to generate .cfi_undefined for unsaved callee-saved registers