bit fields treating negative values should be declared as signed int
* internal.h (struct vm_ifunc_argc): Bit fields are unsigned by default.
For storing nagative values to bit fields, they must be declated as
signed int. Fix multiple test failure observed by 32-bit binaries
compiled with Oracle Developer Studio (Solaris Studio) 12.x on
Solaris 10 on sparc architecture. [Bug #14260]
merge revision(s) 61518: [Backport #14260]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@61660 b2dd03c8-39d4-4d8f-98ff-823fe69b080e