[Bug c++/91292] Mangler incorrectly handles negative numbers in expressions

["ppalka at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91292

Patrick Palka <ppalka at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |ppalka at gcc dot gnu.org

--- Comment #3 from Patrick Palka <ppalka at gcc dot gnu.org> ---
> According to http://itanium-cxx-abi.github.io/cxx-abi/abi.html#expressions , a negative number isn't treated as a negative literal; it is a negated number.  This means that it is mangled as though it were positive, and then its negation is mangled.  So -1 and -(1) are treated the same.

Hmm, but according to
http://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangling.literal the mangling
of a negative integer literal is prefixed with "n", and according to
http://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangle.operator-name the
mangling of -<expr> is prefixed with "ng".  So I don't see why -1 and -(1)
should be given the same mangling.  ISTM GCC is already getting the mangling
right.