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| <h3 class="section">7.1 Symbol Table Format</h3> |
| |
| <p>Each time the assembler encounters a stab directive, it puts |
| each field of the stab into a corresponding field in a symbol table |
| entry of its output file. If the stab contains a string field, the |
| symbol table entry for that stab points to a string table entry |
| containing the string data from the stab. Assembler labels become |
| relocatable addresses. Symbol table entries in a.out have the format: |
| |
| <!-- FIXME: should refer to external, not internal. --> |
| <pre class="example"> struct internal_nlist { |
| unsigned long n_strx; /* index into string table of name */ |
| unsigned char n_type; /* type of symbol */ |
| unsigned char n_other; /* misc info (usually empty) */ |
| unsigned short n_desc; /* description field */ |
| bfd_vma n_value; /* value of symbol */ |
| }; |
| </pre> |
| <p>If the stab has a string, the <code>n_strx</code> field holds the offset in |
| bytes of the string within the string table. The string is terminated |
| by a NUL character. If the stab lacks a string (for example, it was |
| produced by a <code>.stabn</code> or <code>.stabd</code> directive), the |
| <code>n_strx</code> field is zero. |
| |
| <p>Symbol table entries with <code>n_type</code> field values greater than 0x1f |
| originated as stabs generated by the compiler (with one random |
| exception). The other entries were placed in the symbol table of the |
| executable by the assembler or the linker. |
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