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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: C Names and Scopes
Date: Wed, 08 Feb 2017 12:38:04 -0800
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BartC <bc@freeuk.com> writes:
[...]
> For each unique identifier, there is one generic entry in that hash 
> table, joined to a linked list that contains all instances of that name 
> across all functions and blocks. (And, in the original scheme, across 
> all modules. But C likes modules to be compiled entirely independently 
> from each other.)
[...]

Just one small observation.  If two separate scopes happen to define the
same identifier, for example:

    void foo(void) {
        for (int i = 0; i < N; i ++) {
            /* ... */
        }
    }

    void bar(void) {
        for (int i = 0; i < N; i ++) {
            /* ... */
        }
    }

then the two instances of the name "i" are completely independent.
Consider whether it makes sense to include them both in the same linked
list.  (If the symbol table is used for things other than compiling
code, it might well make sense.)

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"