| Re: [AD] Borland C++ compilation errors |
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> The one below is independent from sizeof(long), or it can be done by
> comparing with (long) (((~(unsigned long) 0) >> 1) & ~0xFFFF)
Fixed numbers are explictly definined in the docs as "signed 32-bit
integers, ranging from -32768 to 32767". So I think we should check against
0x7FFF0000.
> It may not work on computers where negative numbers are made by simply
> inverting most significant bit, for example.
Do you know of such CPUs still existing nowadays ?
I remember programming on a 8-bit Motorola 6809 and it already used 2's
complement.
> IMHO, cast to (unsigned long) before shifting makes sure that it is simply
> bitshift with zero filling (though compilers might have their own ideas).
My docs clearly say ANSI C requires bitshifting with zero filling for
positive signed integers.
-Eric