提交: 1134e6ce012575e6d0e99933d0d29cc7978af9af - binutils_os216 (git)

GNU Binutils with patches for OS216

Commit MetaInfo

• 修訂: 1134e6ce012575e6d0e99933d0d29cc7978af9af (tree)
• 時間: 2016-03-09 22:59:31
• 作者: H.J. Lu <hjl.tools@gmai...>
• Commiter: H.J. Lu

Log Message

Treat common symbol in executable as definition

Common symbol in executable is a definition, which overrides definition
from shared objects. When linker sees a new definition from a shared
object, the new dynamic definition should be overridden by the previous
common symbol in executable.

Backport from master

bfd/

PR ld/19579
* elflink.c (_bfd_elf_merge_symbol): Group common symbol checking
together.

* elflink.c (_bfd_elf_merge_symbol): Treat common symbol in
executable as definition if the new definition comes from a
shared library.

ld/

PR ld/19579
* testsuite/ld-elf/pr19579a.c: New file.
* testsuite/ld-elf/pr19579b.c: Likewise.
* testsuite/ld-elf/shared.exp: Run PR ld/19579 test.

Change Summary

• modified: bfd/ChangeLog
• modified: bfd/elflink.c
• modified: ld/ChangeLog
• add: ld/testsuite/ld-elf/pr19579a.c
• add: ld/testsuite/ld-elf/pr19579b.c
• modified: ld/testsuite/ld-elf/shared.exp

差異

--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,18 @@
[phone]  H.J. Lu  <[e-mail]>
+
+	PR ld/19579
+	Backport from master
+	2016-03-08  H.J. Lu  <[e-mail]>
+
+	* elflink.c (_bfd_elf_merge_symbol): Group common symbol checking
+	together.
+
+	2016-03-04  H.J. Lu  <[e-mail]>
+
+	* elflink.c (_bfd_elf_merge_symbol): Treat common symbol in
+	executable as definition if the new definition comes from a
+	shared library.
+
 2016-03-09  Nick Clifton  <[e-mail]>
 	    Alan Modra  <[e-mail]>
 

--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -1485,13 +1485,16 @@ _bfd_elf_merge_symbol (bfd *abfd,
      represent variables; this can cause confusion in principle, but
      any such confusion would seem to indicate an erroneous program or
      shared library.  We also permit a common symbol in a regular
-     object to override a weak symbol in a shared object.  */
+     object to override a weak symbol in a shared object.  A common
+     symbol in executable also overrides a symbol in a shared object.  */
 
   if (newdyn
       && newdef
       && (olddef
 	  || (h->root.type == bfd_link_hash_common
-	      && (newweak || newfunc))))
+	      && (newweak
+		  || newfunc
+		  || (!olddyn && bfd_link_executable (info))))))
     {
       *override = TRUE;
       newdef = FALSE;

--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,13 @@
[phone]  H.J. Lu  <[e-mail]>
+
+	Backport from master
+	2016-03-04  H.J. Lu  <[e-mail]>
+
+	PR ld/19579
+	* testsuite/ld-elf/pr19579a.c: New file.
+	* testsuite/ld-elf/pr19579b.c: Likewise.
+	* testsuite/ld-elf/shared.exp: Run PR ld/19579 test.
+
 2016-03-04  H.J. Lu  <[e-mail]>
 
 	Backport from master

--- /dev/null
+++ b/ld/testsuite/ld-elf/pr19579a.c
@@ -0,0 +1,15 @@
+#include <stdio.h>
+
+int foo[1];
+int bar[2];
+
+extern int *foo_p (void);
+extern int *bar_p (void);
+
+int
+main ()
+{
+  if (foo[0] == 0 && foo == foo_p () && bar[0] == 0 && bar == bar_p ())
+    printf ("PASS\n");
+  return 0;
+}

--- /dev/null
+++ b/ld/testsuite/ld-elf/pr19579b.c
@@ -0,0 +1,14 @@
+int foo[2];
+int bar[2] = { -1, -1 };
+
+int *
+foo_p (void)
+{
+  return foo;
+}
+
+int *
+bar_p (void)
+{
+  return bar;
+}

--- a/ld/testsuite/ld-elf/shared.exp
+++ b/ld/testsuite/ld-elf/shared.exp
@@ -524,6 +524,21 @@ if { [istarget *-*-linux*]
 	    {} \
 	    "libpr2404b.a" \
 	] \
+	[list \
+	    "Build pr19579a.o" \
+	    "" "-fPIE" \
+	    {pr19579a.c} \
+	    {} \
+	    "libpr19579a.a" \
+	] \
+	[list \
+	    "Build libpr19579.so" \
+	    "-shared" \
+	    "-fPIC" \
+	    {pr19579b.c} \
+	    {} \
+	    "libpr19579.so" \
+	] \
     ]
     run_ld_link_exec_tests [] [list \
 	[list \
@@ -580,5 +595,14 @@ if { [istarget *-*-linux*]
 	    "pass.out" \
 	    "-O2 -fPIC -I../bfd" \
 	] \
+	[list \
+	    "Run pr19579" \
+	    "-pie -z text tmpdir/pr19579a.o tmpdir/libpr19579.so" \
+	    "" \
+	    {dummy.c} \
+	    "pr19579" \
+	    "pass.out" \
+	    "-fPIE" \
+	] \
     ]
 }