Re: Boost Spirit X3 Symbol table parser segfaults when in a separate compilation unit

On 28-04-17 13:36, Sigbjørn Lund Olsen wrote:
> I have made a small project which shows what I am trying to achieve and is
> available here: https://github.com/sigbjornlo/spirit_fruit_mcve
I think the problem has been resolved in the X3 develop branch

> My questions:
> - Why does moving the symbol parser to a separate compilation unit cause a
> segmentation fault in this case?
As the analysis confirmed, the symbol table has nothing to do with it.
The expectation point is triggering the use of a `nullptr` rule-name.
That's fixed in https://github.com/boostorg/spirit/pull/229

You should be able to verify this by e.g. replacing the fruit rule with
something like `lexeme["Apples"] >> attr(FRUIT::APPLES) |
lexeme["Oranges"] >> attr(FRUIT::ORANGES)`.

> - What is the "correct" way of making a symbol table reusable in multiple
> parsers? (In the MCVE I obviously only use the fruit parser in one other
> parser, but in my full project I want to use it in several other parsers.

Your way is correct. In order to alleviate SIOF issues, I strongly
suggest making the fruit grammar factory return by reference:
https://github.com/sigbjornlo/spirit_fruit_mcve/pull/1


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