Q34410: Far Pointer Comparisons Don’t Account for Aliases

Article: Q34410
Product(s): See article
Version(s): 5.10   | 5.10
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | | mspl13_c
Last Modified: 12-OCT-1988

The code generated to compare two far pointers for equality does not
account for the possibility of the pointers having different segments
and offsets, yet still pointing to the same location.

This is correct behavior for the compiler. Only huge pointers are
normalized. Near and Far pointers that point into the same segment are
assumed to have the same segment values; any differences between them
must be in the offset.

Normalizing pointers would involve a tremendous performance penalty
under MS-DOS and would be impossible under OS/2 due to the
protected-mode addressing scheme.

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