[PATCH] D72681: [ELF] --exclude-libs: don't assign VER_NDX_LOCAL to undefined symbols

[Fangrui Song via Phabricator via llvm-commits]

MaskRay updated this revision to Diff 238026.
MaskRay added a comment.

Fix comment


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D72681/new/

https://reviews.llvm.org/D72681

Files:
  lld/ELF/Driver.cpp
  lld/test/ELF/exclude-libs-undef.s


Index: lld/test/ELF/exclude-libs-undef.s
===================================================================
--- /dev/null
+++ lld/test/ELF/exclude-libs-undef.s
@@ -0,0 +1,19 @@
+# REQUIRES: x86
+## Test we don't assign VER_NDX_LOCAL to an undefined symbol.
+## If we do, an undefined weak will become non-preemptible,
+## and we will report an error when an R_PLT_PC (optimized to R_PC)
+## references the undefined weak (considered absolute).
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64 %s -o %t.o
+# RUN: rm -f %t.a
+# RUN: llvm-ar rc %t.a %t.o
+# RUN: ld.lld -shared --whole-archive --exclude-libs=ALL %t.a -o %t.so
+# RUN: llvm-readelf --dyn-syms %t.so | FileCheck %s
+
+# CHECK:     1: {{.*}} WEAK DEFAULT UND bar
+# CHECK-NOT: 2:
+
+.globl foo
+.weak bar
+foo:
+  call bar
Index: lld/ELF/Driver.cpp
===================================================================
--- lld/ELF/Driver.cpp
+++ lld/ELF/Driver.cpp
@@ -1375,7 +1375,7 @@
     if (!file->archiveName.empty())
       if (all || libs.count(path::filename(file->archiveName)))
         for (Symbol *sym : file->getSymbols())
-          if (!sym->isLocal() && sym->file == file)
+          if (!sym->isUndefined() && !sym->isLocal() && sym->file == file)
             sym->versionId = VER_NDX_LOCAL;
   };
 


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