Include struct in the %union def with Bison/Yacc

Question

I am trying to include a struct as part of the union with Bison, but I get an error on the \'struct node args\' in %union:

parser.y:17: error: field ‘args’         


        

Answer 1

It comes down to the lame y.tab.h output you get.

You need to fix this by ensuring that "struct node" is defined before you include y.tab.h anywhere.

To do this create a file node.h with the struct definition.

Then include node.h before y.tab.h in your parser.l file, parser.y file as well as any c files you have which include y.tab.h. This is a little annoying.

Alternatively you could change "struct node args" to "struct node* args" since you would not need to know the full type until you go to use it somewhere. Not sure if this would fit with your code.

Either one should work.