[binutils-gdb/binutils-2_31-branch] Always clear h->verinfo.verdef when overriding a dynamic definition

[H.J.Lu]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=76db6c1ac2cb4102e5551ab822afd84d88bb37aa

commit 76db6c1ac2cb4102e5551ab822afd84d88bb37aa
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Fri Aug 10 12:21:58 2018 -0700

    Always clear h->verinfo.verdef when overriding a dynamic definition
    
    When linker defines a symbol to override a dynamic definition, it should
    always clear h->verinfo.verdef so that the symbol won't be associated
    with the version information from the dynamic object.  This happened to
    the symbol "_edata" when creating an unversioned dynamic object linking
    against:
    
    1. libKF5ConfigCore.so.5.49.0
    2. libKF5CoreAddons.so.5.49.0
    3. libKF5I18n.so.5.49.0
    4. libKF5DBusAddons.so.5.49.0
    5. libQt5Xml.so.5.11.1
    6. libQt5DBus.so.5.11.1
    7. libQt5Core.so.5.11.1
    
    Among them
    
    libQt5Xml.so.5.11.1
       299: 000000000003e000     0 NOTYPE  GLOBAL DEFAULT   18 _edata@@Qt_5
    libQt5DBus.so.5.11.1
       597: 0000000000092018     0 NOTYPE  GLOBAL DEFAULT   18 _edata@@Qt_5
    libQt5Core.so.5.11.1
      2292: 00000000004df640     0 NOTYPE  GLOBAL DEFAULT   21 _edata@Qt_5
      2293: 00000000004df640     0 NOTYPE  GLOBAL DEFAULT   21 _edata@Qt_5
    
    The problem is triggered by 2 duplicated entries of _edata@Qt_5 in
    libQt5Core.so.5.11.1 which was created by gold.  Before this commit,
    ld created the dynamic object with "_edata" in its dynamic symbol table
    which was linker defined and associated with the version information
    from libQt5Core.so.5.11.1.  The code in question was there when the
    binutils source was imported to sourceware.org.  When such a dynamic
    object was used later, we got:
    
    /usr/bin/ld: bin/libKF5Service.so.5.49.0: _edata: invalid version 21 (max 0)
    /usr/bin/ld: bin/libKF5Service.so.5.49.0: error adding symbols: bad value
    
    Tested with many ELF targets.
    
    	PR ld/23499
    	* elflink.c (bfd_elf_record_link_assignment): Always clear
    	h->verinfo.verdef when overriding a dynamic definition.
    
    (cherry picked from commit 48e30f5238c70e738f44474d595c476ef4e4ec38)

Diff:
---
 bfd/ChangeLog |  6 ++++++
 bfd/elflink.c | 12 +++++-------
 2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 7364bed..f0eb899 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,9 @@
+2018-09-12  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/23499
+	* elflink.c (bfd_elf_record_link_assignment): Always clear
+	h->verinfo.verdef when overriding a dynamic definition.
+
 2018-08-12  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR ld/23428
diff --git a/bfd/elflink.c b/bfd/elflink.c
index b24fb95..02618be 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -686,13 +686,11 @@ bfd_elf_record_link_assignment (bfd *output_bfd,
       && !h->def_regular)
     h->root.type = bfd_link_hash_undefined;
 
-  /* If this symbol is not being provided by the linker script, and it is
-     currently defined by a dynamic object, but not by a regular object,
-     then clear out any version information because the symbol will not be
-     associated with the dynamic object any more.  */
-  if (!provide
-      && h->def_dynamic
-      && !h->def_regular)
+  /* If this symbol is currently defined by a dynamic object, but not
+     by a regular object, then clear out any version information because
+     the symbol will not be associated with the dynamic object any
+     more.  */
+  if (h->def_dynamic && !h->def_regular)
     h->verinfo.verdef = NULL;
 
   /* Make sure this symbol is not garbage collected.  */