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Re: [PATCH] PR libstdc++/13045 / C++ demangler, floating values and function pointer type return type postfix fix.


Ian Lance Taylor <ian@wasabisystems.com> writes:

| 2) The same floating point number has multiple representations as a
|    C99 hex floating point constant.

Not so many, actually.  I believe we can easily specify a normal form
for such a constant -- which would mean that equality can be reduced
to string-compare. 

|  The ABI would have to be written
|    to constrain this in some way, such as requiring that the exponent
|    be a multiple of 4 and the significand have no more than three
|    trailing zero bits (i.e., no trailing hex zero digit).

No leading zeros for the exponent, no trailing zeros for the
mantissa. I do not think the mulitple of 4 requirement is necessary.

-- Gaby


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