[llvm] r347481 - [Object] Also treat STB_GNU_UNIQUE symbols as exported to other DSO

[Fangrui Song via llvm-commits]

Author: maskray
Date: Thu Nov 22 17:33:19 2018
New Revision: 347481

URL: http://llvm.org/viewvc/llvm-project?rev=347481&view=rev
Log:
[Object] Also treat STB_GNU_UNIQUE symbols as exported to other DSO

All of STB_GLOBAL/STB_WEAK/STB_GNU_UNIQUE are treated as export symbols, see:

glibc/elf/dl-lookup.c:do_lookup_x
musl/ldso/dynlink.c OK_BINDS

Though ld.so does not read binding, the currently used STV_DEFAULT or STV_PROTECTED is a good emulation of linker behavior.

Modified:
    llvm/trunk/include/llvm/Object/ELFObjectFile.h

Modified: llvm/trunk/include/llvm/Object/ELFObjectFile.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Object/ELFObjectFile.h?rev=347481&r1=347480&r2=347481&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Object/ELFObjectFile.h (original)
+++ llvm/trunk/include/llvm/Object/ELFObjectFile.h Thu Nov 22 17:33:19 2018
@@ -333,9 +333,10 @@ protected:
     // A symbol is exported if its binding is either GLOBAL or WEAK, and its
     // visibility is either DEFAULT or PROTECTED. All other symbols are not
     // exported.
-    return ((Binding == ELF::STB_GLOBAL || Binding == ELF::STB_WEAK) &&
-            (Visibility == ELF::STV_DEFAULT ||
-             Visibility == ELF::STV_PROTECTED));
+    return (
+        (Binding == ELF::STB_GLOBAL || Binding == ELF::STB_WEAK ||
+         Binding == ELF::STB_GNU_UNIQUE) &&
+        (Visibility == ELF::STV_DEFAULT || Visibility == ELF::STV_PROTECTED));
   }
 
   // This flag is used for classof, to distinguish ELFObjectFile from