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.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 20aa4f3c874ad416ff09154847502e579033ed0c..a62a8546029c853080e7bffb36e6bb5513fe02fb 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,9 @@
+2018-08-10  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.
+
 2018-08-10  H.J. Lu  <hongjiu.lu@intel.com>
 
        PR binutils/23494

diff --git a/bfd/elflink.c b/bfd/elflink.c
index b24fb95848d6990a2496600d910a400b2648a58c..02618bed8fea01db1f3e24d92b53aaa6aac1ff4f 100644 (file)
--- 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.  */