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Symbol Attributes for COFF
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   The COFF format supports a multitude of auxiliary symbol attributes;
like the primary symbol attributes, they are set between `.def' and
`.endef' directives.

Primary Attributes
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   The symbol name is set with `.def'; the value and type,
respectively, with `.val' and `.type'.

Auxiliary Attributes
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   The `as' directives `.dim', `.line', `.scl', `.size', and `.tag' can
generate auxiliary symbol table information for COFF.