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<p><span style="color: rgb(33, 33, 33); font-size: 12pt;">>> </span><br>
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<div dir="ltr">>>Looks like we should do something for them, but can you describe what we should do? I can't find a simple rule to describe the behavior of GNU linkers.<br>
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<div dir="ltr">> </div>
<div dir="ltr">>Description looks to be simple:<br>
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<div dir="ltr">> </div>
<div dir="ltr">>"The linker uses a simple heuristic to do this. It attempts to place orphan sections after non-orphan sections of the same attribute, such as code vs data, loadable vs >non-loadable, etc. If there is not enough room to do this then it places
at the end of the file."<br>
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<span style="font-size:12pt">>(<a href="https://sourceware.org/binutils/docs/ld/Orphan-Sections.html">https://sourceware.org/binutils/docs/ld/Orphan-Sections.html</a>)</span><br>
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<div class="gmail_quote"><span style="font-size:12pt">> </span></div>
<div class="gmail_quote"><span style="font-size:12pt">>George.</span></div>
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<div class="gmail_quote"><span style="font-size:12pt">And behavior of ld and gold differers here. ld seems makes simple thing: it just tries to place orphan sections after sections of the same attribute and does not watch if there is room or not:</span></div>
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.global _start</div>
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_start:</div>
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nop</div>
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.section .foo1, "a"</div>
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foo1:</div>
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.long 1</div>
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.section .foo2, "a"</div>
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foo2:</div>
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.long 1</div>
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.section .foo3, "a"<br>
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foo3:</div>
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.long 1</div>
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.section .bar1, "aw"</div>
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bar1:</div>
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.long 1<br>
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<div>SECTIONS { <br>
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<div>. = 0x1000;</div>
<div>.foo1 : { *(.foo1) }</div>
<div>.foo2 : { *(.foo2) }<br>
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<div>. = 0x1009;</div>
<div>.bar1 : { *(.bar1) }<br>
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<div>}<br>
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<div><span style="font-size: 12pt;">++ ld start.o -script linker.script -o out</span>
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<div>ld: section .foo3 loaded at [0000000000001009,000000000000100c] overlaps section .bar1 loaded at [0000000000001009,000000000000100c]</div>
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<div>gold does not show any errors, but its output seems to be broken for my eye:<br>
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<div> [ 1] .foo1 PROGBITS 0000000000001000 00001000</div>
<div> 0000000000000004 0000000000000000 A 0 0 1</div>
<div> [ 2] .foo2 PROGBITS 0000000000001004 00001004</div>
<div> 0000000000000004 0000000000000000 A 0 0 1</div>
<div> [ 3] .text PROGBITS 000000000000100c 0000100c</div>
<div> 0000000000000001 0000000000000000 AX 0 0 4</div>
<div> [ 4] .foo3 PROGBITS 000000000000100d 0000100d</div>
<div> 0000000000000004 0000000000000000 A 0 0 1</div>
<div> [ 5] .bar1 PROGBITS 0000000000001030 00001030</div>
<div> 0000000000000004 0000000000000000 WA 0 0 1</div>
<div><br>
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<div>Making some room helps ld to work:<br>
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SECTIONS { <br>
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. = 0x1000;</div>
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.foo1 : { *(.foo1) }</div>
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.foo2 : { *(.foo2) }<br>
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. = 0x1100;</div>
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.bar1 : { *(.bar1) }<br>
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}<br>
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ld output:<br>
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<div> [ 1] .text PROGBITS 0000000000001000 00001000</div>
<div> 0000000000000001 0000000000000000 AX 0 0 4</div>
<div> [ 2] .foo1 PROGBITS 0000000000001001 00001001</div>
<div> 0000000000000004 0000000000000000 A 0 0 1</div>
<div> [ 3] .foo2 PROGBITS 0000000000001005 00001005</div>
<div> 0000000000000004 0000000000000000 A 0 0 1</div>
<div> [ 4] .foo3 PROGBITS 0000000000001009 00001009</div>
<div> 0000000000000004 0000000000000000 A 0 0 1</div>
<div> [ 5] .bar1 PROGBITS 0000000000001100 00001100</div>
<div> 0000000000000004 0000000000000000 WA 0 0 1</div>
<div><br>
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<div>So I would start with ld behavior. If I am not missing something ld way would be<br>
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<div>easy to implement and that should keep code simple at the same way.<br>
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<div>I`ll try to prepare a patch.</div>
<div><br>
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<div>George.<br>
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