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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - llvm-objcopy should remove .symtab_shndx if enough symbols are removed"
href="https://bugs.llvm.org/show_bug.cgi?id=49364">49364</a>
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<th>Summary</th>
<td>llvm-objcopy should remove .symtab_shndx if enough symbols are removed
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<th>Product</th>
<td>tools
</td>
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<th>Version</th>
<td>trunk
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Windows NT
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>enhancement
</td>
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<th>Priority</th>
<td>P
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<th>Component</th>
<td>llvm-objcopy/strip
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<th>Assignee</th>
<td>unassignedbugs@nondot.org
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<th>Reporter</th>
<td>jh7370.2008@my.bristol.ac.uk
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<th>CC</th>
<td>alexander.v.shaposhnikov@gmail.com, jake.h.ehrlich@gmail.com, jh7370.2008@my.bristol.ac.uk, llvm-bugs@lists.llvm.org, rupprecht@google.com
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<pre>llvm-objcopy is intended to emit the SHT_SYMTAB_SHNDX table if and only if it
is required. The table is required if at least one section with an index >=
SHN_LORESERVE has at least one symbol.
When adding/removing sections, or when adding new symbols, this process appears
to work correctly. However, if all symbols in sections with index >=
SHN_LORESERVE are removed (but not the sections themselves), llvm-objcopy still
emits the .symtab_shndx section. The problem is that the `HasSymbol` section
member, which is used to identify whether a section with index >= SHN_LORESERVE
should cause emission of the SHT_SYMTAB_SHNDX section, is not updated after a
symbol has been removed. Consequently, the check to see whether the table
should be added spuriously thinks it should.
Running llvm-objcopy without any switches on the output of an operation that
should have removed the table, but didn't, results in the table being
discarded.</pre>
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