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heap_4 and 16BitDOS Port

Posted by pronkin on July 15, 2016

I' m using official OpenWatcom 16BitDOS port and found that in heap4.c (and heap5.c) size_t is used for address arithmetic and aligning (FreeRTOS V9.0.0). But casting far pointer to size_t always result zero in segment memory model: ~~~ /* Ensure the heap starts on a correctly aligned boundary. */ uxAddress = ( size_t ) ucHeap; ~~~ the result that heap placed at zero address (applicashon crash).

When I made some modificationsn in heap init function such as: 1. change uxAddress to long 2. start using FP_SEG and FP_OFF macroses for convert far pointer to/from absolute address

heap start working correctly.

It's easy to reproduce this with openwatcom and DOSBox.

Does this port still supported or I missed somethig that I can't use heap4 or heap5 memory mangement with it? or heap init code must be refactored to be more portable?

heap_4 and 16BitDOS Port

Posted by rtel on July 15, 2016

That demo was actually removed in the V9.0.0 release, although it is still available in older releases available from the SourceForge web site. It has probably never been tested with heap_4 or 5.

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