I think I see a few issues in your code, but without the complete source I can't conclusively say what your problem might be.
First: > if(strcmp($<blOperator>2, "+")) Just to be sure: you know strcmp returns 0 when the strings match, right? I ask because it looks like you're trying to convert "+" to "add", and this logic will convert it to "sub". Next: > strcpy($<blOperator>2, "add"); I don't think it's really safe to write to a $k variable. Granted if you own its type you can do whatever you want, but that's not the case here. You show that it's created by strdup, but if the value is "+" then the char string is only two characters long -- you can't safely strcpy the four-character "add" string to that location. Next: > | ( expr) As Hans mentioned, there's a default action here to return the $1 value as $$, and that's not what you want. You'll need to make an explicit action to return $2 instead. Oh, I see he just posted that. :) Related to that, you don't assign $$ in the "expr" rule at all. Instead you seem to be trying to overwrite $1. Since "expr" is recursive, you'll have to assign $$ in order to propagate values correctly up the stack. Hope that helps.. :/ -Chris On Wed, Aug 4, 2010 at 9:39 AM, Sasan Forghani <sasanforgh...@gmail.com>wrote: > Thank you for the information. However, how does this relate to the > $<blIdentifier> problem I am having. To be more specific, the problem > where > the $<blIdentifier> of the ASSIGNMENT production ends up with the same > value > of the ( expr ) production. > > On Wed, Aug 4, 2010 at 9:04 AM, Hans Aberg <haber...@telia.com> wrote: > > > On 4 Aug 2010, at 14:17, Sasan Forghani wrote: > > > > I apologize for my lack of understanding. You said the next step is to > >> clean it up in the actions... please clarify? > >> > > > > When you allocate stuff using malloc, strdup, etc. when pointer is not > used > > anymore, to avoid memory leak, one must apply free(). For example, an > action > > might look like > > $$ = malloc(...) // pr something > > // copy over some stuff from the $k values. > > Now the, $k values are not used anymore - only $$, so they must be > cleaned > > up using free(). > > > > This works if you do not want to do error recovery. For that there is a > > special function (see the Bison manual). > > > > I do not program in C, but C++, where the language is taking care of > this. > > So perhaps some else might give better examples. > > > _______________________________________________ > help-bison@gnu.org http://lists.gnu.org/mailman/listinfo/help-bison > _______________________________________________ help-bison@gnu.org http://lists.gnu.org/mailman/listinfo/help-bison
