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<h4 class="subsection">9.38.4 RISC-V Object Attribute</h4>
<p><a name="index-Object-Attribute_002c-RISC_002dV-2001"></a>
RISC-V attributes have a string value if the tag number is odd and an integer
value if the tag number is even.
<dl>
<dt><span class="roman">Tag_RISCV_stack_align (4)</span><dd>Tag_RISCV_strict_align records the N-byte stack alignment for this object. The
default value is 16 for RV32I or RV64I, and 4 for RV32E.
<p>The smallest value will be used if object files with different
Tag_RISCV_stack_align values are merged.
<br><dt><span class="roman">Tag_RISCV_arch (5)</span><dd>Tag_RISCV_arch contains a string for the target architecture taken from the
option <samp><span class="option">-march</span></samp>. Different architectures will be integrated into a
superset when object files are merged.
<p>Note that the version information of the target architecture must be presented
explicitly in the attribute and abbreviations must be expanded. The version
information, if not given by <samp><span class="option">-march</span></samp>, must be in accordance with the
default specified by the tool. For example, the architecture <code>RV32I</code> has
to be recorded in the attribute as <code>RV32I2P0</code> in which <code>2P0</code> stands
for the default version of its base ISA. On the other hand, the architecture
<code>RV32G</code> has to be presented as <code>RV32I2P0_M2P0_A2P0_F2P0_D2P0</code> in
which the abbreviation <code>G</code> is expanded to the <code>IMAFD</code> combination
with default versions of the standard extensions.
<br><dt><span class="roman">Tag_RISCV_unaligned_access (6)</span><dd>Tag_RISCV_unaligned_access is 0 for files that do not allow any unaligned
memory accesses, and 1 for files that do allow unaligned memory accesses.
<br><dt><span class="roman">Tag_RISCV_priv_spec (8)</span><br><dt><span class="roman">Tag_RISCV_priv_spec_minor (10)</span><br><dt><span class="roman">Tag_RISCV_priv_spec_revision (12)</span><dd>Tag_RISCV_priv_spec contains the major/minor/revision version information of
the privileged specification. It will report errors if object files of
different privileged specification versions are merged.
</dl>
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