[lld] [ELF] Align the end of PT_GNU_RELRO associated PT_LOAD to a common-page-size boundary (PR #66042)

[Fangrui Song via llvm-commits]

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@@ -920,7 +929,9 @@ static unsigned getSectionRank(const OutputSection &osec) {
     // TLS sections directly before the other RELRO sections.
     if (!(osec.flags & SHF_TLS))
       rank |= RF_NOT_TLS;
-    if (!isRelroSection(&osec))
+    if (isRelroSection(&osec))
+      osec.relro = true;
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MaskRay wrote:

`ScriptParser::readSections` clears `relro` if there is no `DATA_SEGMENT_RELRO_END`.

After `getSectionRank`, `relro` has changed its meaning: whether the section is RELRO, to be checked in `seenRelro |= sec->relro && sec->type != SHT_NOBITS;`.

In the absence of `DATA_SEGMENT_RELRO_END`, this code is still correct.

https://github.com/llvm/llvm-project/pull/66042