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From: Archie Cobbs <archie@tribe.com>
Message-Id: <199509060022.RAA10570@bubba.tribe.com>
Subject: multiple variable definitions in object files
To: questions@freebsd.org
Date: Tue, 5 Sep 1995 17:22:46 -0700 (PDT)
Cc: archie@tribe.com
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Hello,

Can someone explain why the linker allows multiple definitions of
a variable to be linked together without complaining or warning?

I found this surprising... I thought this was a no-no. At least it
has always caused errors in the past it seems.

I didn't see any relevant info in the ld(1) man page.

For example:

======== foo.c ============

    int global;

    main()
    {
     global = 2;
     printf("foo: global = %d\n", global);
     bar();
    }

======== bar.c ============

    float global;

    bar()
    {
     printf("bar: global = %f\n", global);
    }

======== compile with ==========

    $ cc -o foobar foo.c bar.c
    $ foobar
    foo: global = 2
    bar: global = 0.000000
    $


Thanks for any insight,
-Archie

_______________________________________________________________________________
Archie L. Cobbs, archie@tribe.com  *  Tribe Computer Works http://www.tribe.com