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The alternative to recursion is either a linked list, a fixed size array, or a growing array</div>
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In RPN evaluation, the code often looks like this, because you don't need the full power and cost of recursion</div>
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ops : array of operators</div>
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stack : stack of operands</div>
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top = 0</div>
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for op in instructionStream do</div>
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caseOf nOperands(op.code)</div>
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alt add:</div>
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stack[top - 1] += stack[top]</div>
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top = top - 1</div>
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alt int:</div>
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top = top+1</div>
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stack[top] = op.int</div>
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...</div>
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Don't forget to check for malformed expressions, which could result in h/w stack corruption due to indexing outside 'stack'</div>
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/Bevin</div>
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...<br>
<br>
I am building an RPN expression evaluator for the uCPU assembler; I<br>
can't see any other way to go other than to use recursion to do the<br>
nested processing that I wish.<br>
<br>
Currently using "gcc version 12.2.0 (MinGW-W64 x86_64-ucrt-posix-seh,<br>
built by Brecht Sanders)"<br>
<br>
The first call of the recursed function worked fine, but crashes upon exit.<br>
<br>
It could be that the compiler is not generating re-entrant code. The<br>
only switch I have used is -O0 to disable compiler optimization.<br>
<br>
Are there any other switches for GCC that I need to use/be aware of ?<br>
<br>
Thanks, Mark<br>
<br>
...</div>
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