From 59ea52933d5a1f5e274b8fbe72183ff1a8043724 Mon Sep 17 00:00:00 2001
From: Rui Ueyama <ruiu@bluewhale.systems>
Date: Mon, 24 Oct 2022 06:46:57 +0800
Subject: [PATCH] [ELF] Honor section alignment when creating copy relocations

---
 elf/input-files.cc            | 9 ++++-----
 test/elf/copyrel-alignment.sh | 2 +-
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/elf/input-files.cc b/elf/input-files.cc
index 9993bf60..b3276792 100644
--- a/elf/input-files.cc
+++ b/elf/input-files.cc
@@ -1488,11 +1488,10 @@ std::vector<Symbol<E> *> SharedFile<E>::find_aliases(Symbol<E> *sym) {
 template <typename E>
 i64 SharedFile<E>::get_alignment(Symbol<E> *sym) {
   ElfShdr<E> &shdr = this->elf_sections[sym->esym().st_shndx];
-  i64 p2align = std::min(std::countr_zero<u64>(sym->value),
-                         std::countr_zero<u64>(shdr.sh_addralign));
-
-  // We do not want a ridiculously large alignment. Cap it arbitrary at 64.
-  return std::min(64, 1 << p2align);
+  i64 align = std::max<i64>(1, shdr.sh_addralign);
+  if (sym->value)
+    align = std::min<i64>(align, 1LL << std::countr_zero(sym->value));
+  return align;
 }
 
 template <typename E>
diff --git a/test/elf/copyrel-alignment.sh b/test/elf/copyrel-alignment.sh
index d0d11f2c..7f23af1e 100755
--- a/test/elf/copyrel-alignment.sh
+++ b/test/elf/copyrel-alignment.sh
@@ -32,4 +32,4 @@ readelf -W --sections $t/exe2 | grep -q '\.copyrel.* 8$'
 
 $CC -B. -o $t/exe3 $t/d.o $t/c.so -no-pie
 $QEMU $t/exe3 > /dev/null
-readelf -W --sections $t/exe3 | grep -q '\.copyrel.* 64$'
+readelf -W --sections $t/exe3 | grep -q '\.copyrel.* 256$'