Allow emission of names that start with an underscore.  This is needed to interface with code that uses symbols in the ansi-c protected namespace.  In most cases this comes from system header files, such as stdio.h.  In particular, without this change, a reference to the __iob symbol is mangled into ll_iob, which is not resolved by libc.
Allow emission of names that start with an underscore.  This is needed to
interface with code that uses symbols in the ansi-c protected namespace.  In
most cases this comes from system header files, such as stdio.h.  In particular,
without this change, a reference to the __iob symbol is mangled into ll_iob,
which is not resolved by libc.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@4165 91177308-0d34-0410-b5e6-96231b3b80d8

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