[PATCH] D101334: [llvm-objcopy] Always check for indirect symbol references before stripping

[Jez Ng via Phabricator via llvm-commits]

int3 created this revision.
int3 added reviewers: smeenai, alexshap, jhenderson, rmaz.
Herald added a reviewer: rupprecht.
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Previously, we only checked for those references when doing
`--strip-all`, but not when doing `--discard-all`. I believe that this
didn't cause issues with ld64-generated binaries as they did not create
indirect symbol references to local symbols (which `--discard-all`
removes). However LLD does emit these, exposing the issue.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D101334

Files:
  llvm/test/tools/llvm-objcopy/MachO/discard-all.test
  llvm/tools/llvm-objcopy/MachO/MachOObjcopy.cpp


Index: llvm/tools/llvm-objcopy/MachO/MachOObjcopy.cpp
===================================================================
--- llvm/tools/llvm-objcopy/MachO/MachOObjcopy.cpp
+++ llvm/tools/llvm-objcopy/MachO/MachOObjcopy.cpp
@@ -361,9 +361,7 @@
     return E;
 
   // Mark symbols to determine which symbols are still needed.
-  if (Config.StripAll)
-    markSymbols(Config, Obj);
-
+  markSymbols(Config, Obj);
   updateAndRemoveSymbols(Config, Obj);
 
   if (Config.StripAll)
Index: llvm/test/tools/llvm-objcopy/MachO/discard-all.test
===================================================================
--- llvm/test/tools/llvm-objcopy/MachO/discard-all.test
+++ llvm/test/tools/llvm-objcopy/MachO/discard-all.test
@@ -17,6 +17,10 @@
 # RUN: llvm-strip -x %t
 # RUN: cmp %t2 %t
 
+## FIXME: We should also check that we don't discard symbols that are referenced
+## by the indirect symbol table. However, yaml2obj currently lacks support for
+## the indirect symbol table.
+
 # CHECK:       Symbols [
 # CHECK-NEXT:    Symbol {
 # CHECK-NEXT:      Name: _b (1)


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