%left is not working

[Sasan Forghani]

Hello,

I have been writing a simple compiler for a CS class and have run into a few
problems that I can't figure out how to solve.  %left does not seem to be
working as Bison is derivating immediately.

For example:

a := b + c + d

expr : expr ADDOP expr
expr: ref_name
ref_name: IDENTIFIER

ADDOP is specified with the %left

The directed translation in parse tree representation is

 E
E         +         E
R         E         +         E
b          c                    d

Since ADDOP is specified with % left shouldn't the tree look like:

E
E        +         E
E        +        E         R
R                  R         d
b                   c

Another problem I have run into is sending data back when a recursive call
is finished. If the input is a := (b + c) + d, the code I have is as
follows:

stmt : ref_name BL_ASSIGNMENT expr {

    fprintf(ptrToIrFile, "mov         %s          %s\n", $<blIdentifier>3,
                    $<blIdentifier>1);
}

expr : expr BL_ADDOP expr {

    if(strcmp($<blOperator>2, "+"))
        strcpy($<blOperator>2, "add");
    else
        strcpy($<blOperator>2, "sub");

    char bufferT[6];
    changeToString(++amtOfTemps, "T", bufferT);
    fprintf(ptrToIrFile, "%s         %s          %s          %s\n",
                    $<blOperator>2, $<blIdentifier>1, $<blIdentifier>3,
bufferT);

    strcpy($<blIdentifier>1, bufferT);
}

| ( expr)

as long as there isn't ( expr ) in the input input move up without problem.
However once input does have an ( expr) part, $<blIdentifier>1 at the ADDOP
level has the value of $<blIdentifier>1 at the ASSIGNMENT level.  When I add
the following action to the ( expr ) production- {strcpy($<blIdentifier>1,
$<blIdentifier>2);}, $<blIdentifier>1 at the ADDOP level has the correct
value but then the $<blIdentifier>1 at the ASSIGNMENT level value is what I
changed $<blIdentifier>1 to be at the ( expr ) level.  I'm very confused.
Please help.