Posted by Chung Leong on 01/24/06 17:45

Oli Filth wrote:

> As a side-note:
> I don't like the fact that even basic PHP code isn't portable between
> platforms, i.e. it doesn't abstract away differences in platform bitwise
> implementations of signed values.

I don't really see why the operation would be platform dependent. If I
remember correctly, a long is defined as 32 bit. Int is the one that
varies between architectures. In PHP, a convert from double to integer
is done by the DVAL_TO_LVAL macro, which is defined as:

(l) = (d) > LONG_MAX ? (unsigned long) (d) : (long) (d)

A cast to long should be the same even on a 64 bit OS/CPU.

I wonder if it's a difference in the compiler or C library. Typically a
cast from a float to a long is handled with a call to ftol(). Maybe the
overflow behavior is different.

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