From e0c67abf26febfdecd106fec37d7c51bb13741bf Mon Sep 17 00:00:00 2001
From: Felix Kellenbenz <107758057+felixkellenbenz@users.noreply.github.com>
Date: Wed, 24 Jan 2024 09:12:16 +0100
Subject: [PATCH] [llvm-objcopy] Don't remove .gnu_debuglink section when using
 --strip-all (#78919)

This fixes the issue mentioned here:
https://github.com/llvm/llvm-project/issues/57407
It prevents `llvm-objcopy` from removing the `.gnu _debuglink` section
when used with the `--strip-all` flag. Since `--strip-all` is the
default of `llvm-strip` the patch also prevents `llvm-strip` from
removing the `.gnu_debuglink` section.
---
 llvm/lib/ObjCopy/ELF/ELFObjcopy.cpp             | 2 ++
 llvm/test/tools/llvm-objcopy/ELF/strip-all.test | 5 ++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/ObjCopy/ELF/ELFObjcopy.cpp b/llvm/lib/ObjCopy/ELF/ELFObjcopy.cpp
index dfe843e1d4b7..3c25d2f26ead 100644
--- a/llvm/lib/ObjCopy/ELF/ELFObjcopy.cpp
+++ b/llvm/lib/ObjCopy/ELF/ELFObjcopy.cpp
@@ -434,6 +434,8 @@ static Error replaceAndRemoveSections(const CommonConfig &Config,
         return false;
       if (StringRef(Sec.Name).startswith(".gnu.warning"))
         return false;
+      if (StringRef(Sec.Name).startswith(".gnu_debuglink"))
+        return false;
       // We keep the .ARM.attribute section to maintain compatibility
       // with Debian derived distributions. This is a bug in their
       // patchset as documented here:
diff --git a/llvm/test/tools/llvm-objcopy/ELF/strip-all.test b/llvm/test/tools/llvm-objcopy/ELF/strip-all.test
index 20f3c9addf55..ba27a3509c6a 100644
--- a/llvm/test/tools/llvm-objcopy/ELF/strip-all.test
+++ b/llvm/test/tools/llvm-objcopy/ELF/strip-all.test
@@ -68,16 +68,19 @@ Sections:
     Flags:           [ ]
   - Name:            .gnu.warning.foo
     Type:            SHT_PROGBITS
+  - Name:            .gnu_debuglink
+    Type:            SHT_PROGBITS
 ProgramHeaders:
   # Use an arbitrary segment type to show that the segment type is unimportant.
   - Type:     0x61234567
     FirstSec: non_alloc_in_segment
     LastSec:  non_alloc_in_segment
 
-# CHECK: SectionHeaderCount: 6
+# CHECK: SectionHeaderCount: 7
 
 # CHECK: Name: non_alloc_in_segment
 # CHECK: Name: .bss
 # CHECK: Name: .text
 # CHECK: Name: .gnu.warning.foo
+# CHECK: Name: .gnu_debuglink
 # CHECK: Name: .shstrtab
-- 
Gitee