Re: PATCH: PR ld/13195: -ffunction-sections -Wl,--gc-sections failure with symbol versioning

["H.J. Lu" <hongjiu dot lu at intel dot com>]

On Sat, Sep 17, 2011 at 03:41:50PM -0700, H.J. Lu wrote:
> On Fri, Sep 16, 2011 at 03:57:29PM -0700, H.J. Lu wrote:
> > Fix for:
> > 
> > http://sourceware.org/bugzilla/show_bug.cgi?id=13177
> > 
> > caused:
> > 
> > http://www.sourceware.org/bugzilla/show_bug.cgi?id=13195
> > 
> > The problem is we don't always set dynamic_def when setting def_dynamic.
> > We can fix it by
> > 
> > 1. Always set dynamic_def when setting def_dynamic.  Or
> > 2. Check both dynamic_def and def_dynamic.
> > 
> > I am enclosing both patches here.  Is any of them OK to install?
> > 
> 
> I found anothe problem with --gc-sections and symbol versioning. If
> a symbol has ELF_VER_CHR, it is global.  This patch fixes it and
> always sets dynamic_def when setting def_dynamic.
> 

Here is the updated patch with an additional testcase.  OK to install?

Thanks.


H.J.
---
bfd/

2011-09-28  H.J. Lu  <hongjiu.lu@intel.com>

	PR ld/13195
	* elflink.c (_bfd_elf_merge_symbol): Don't set dynamic_def when
	clearing def_dynamic.
	(elf_link_add_object_symbols): Likewise.  Set dynamic_def when
	setting def_dynamic.
	(bfd_elf_gc_mark_dynamic_ref_symbol): Check if a symbol is
	versioned.

ld/testsuite/

2011-09-28  H.J. Lu  <hongjiu.lu@intel.com>

	PR ld/13195
	* ld-elf/elf.exp: Add a C link testcase for PR ld/13195.

	* ld-elf/pr13195.c: New.
	* ld-elf/pr13195.d: Likewise.
	* ld-elf/pr13195.s: Likewise.
	* ld-elf/pr13195.t: Likewise.

diff --git a/bfd/elflink.c b/bfd/elflink.c
index 9ccf37d..a15ad27 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -1238,7 +1238,6 @@ _bfd_elf_merge_symbol (bfd *abfd,
 	{
 	  h->def_dynamic = 0;
 	  h->ref_dynamic = 1;
-	  h->dynamic_def = 1;
 	}
       /* FIXME: Should we check type and size for protected symbol?  */
       h->size = 0;
@@ -4353,7 +4352,6 @@ error_free_dyn:
 		    {
 		      h->def_dynamic = 0;
 		      h->ref_dynamic = 1;
-		      h->dynamic_def = 1;
 		    }
 		}
 	      if (! info->executable
@@ -4366,7 +4364,10 @@ error_free_dyn:
 	      if (! definition)
 		h->ref_dynamic = 1;
 	      else
-		h->def_dynamic = 1;
+		{
+		  h->def_dynamic = 1;
+		  h->dynamic_def = 1;
+		}
 	      if (h->def_regular
 		  || h->ref_regular
 		  || (h->u.weakdef != NULL
@@ -11914,8 +11915,9 @@ bfd_elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h, void *inf)
 	      && h->def_regular
 	      && ELF_ST_VISIBILITY (h->other) != STV_INTERNAL
 	      && ELF_ST_VISIBILITY (h->other) != STV_HIDDEN
-	      && !bfd_hide_sym_by_version (info->version_info,
-					   h->root.root.string))))
+	      && (strchr (h->root.root.string, ELF_VER_CHR) != NULL
+		  || !bfd_hide_sym_by_version (info->version_info,
+					       h->root.root.string)))))
     h->root.u.def.section->flags |= SEC_KEEP;
 
   return TRUE;
diff --git a/ld/testsuite/ld-elf/elf.exp b/ld/testsuite/ld-elf/elf.exp
index 4a00b81..866c866 100644
--- a/ld/testsuite/ld-elf/elf.exp
+++ b/ld/testsuite/ld-elf/elf.exp
@@ -138,6 +138,11 @@ if ![isnative] {
     return
 }
 
+run_cc_link_tests {
+    {"PR ld/13195" "-Wl,--gc-sections" ""
+     {pr13195.c} {} "pr13195"}
+}
+
 set array_tests {
     {"preinit array" "" "" {preinit.c} "preinit" "preinit.out"}
     {"init array" "" "" {init.c} "init" "init.out"}
diff --git a/ld/testsuite/ld-elf/pr13195.c b/ld/testsuite/ld-elf/pr13195.c
new file mode 100644
index 0000000..a9bce4a
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr13195.c
@@ -0,0 +1,5 @@
+int
+main ()
+{
+  return 0;
+}
diff --git a/ld/testsuite/ld-elf/pr13195.d b/ld/testsuite/ld-elf/pr13195.d
new file mode 100644
index 0000000..796102b
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr13195.d
@@ -0,0 +1,10 @@
+#ld: --gc-sections -shared -version-script pr13195.t
+#readelf: -s --wide -D
+#target: *-*-linux* *-*-gnu*
+#notarget: arc-*-* d30v-*-* dlx-*-* i960-*-* or32-*-* pj*-*-*
+#notarget: hppa64-*-* i370-*-* i860-*-* ia64-*-* mep-*-* mn10200-*-*
+# generic linker targets don't support --gc-sections, nor do a bunch of others
+
+#...
+ +[0-9]+ +[0-9]+: +[0-9a-f]+ +[0-9]+ +FUNC +GLOBAL +DEFAULT +[1-9]+ foo
+#pass
diff --git a/ld/testsuite/ld-elf/pr13195.s b/ld/testsuite/ld-elf/pr13195.s
new file mode 100644
index 0000000..409b5af
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr13195.s
@@ -0,0 +1,6 @@
+	.section .text.new_foo,"ax",%progbits
+	.globl	new_foo
+	.type	new_foo, %function
+new_foo:
+	.byte 0
+	.symver new_foo,foo@@VERS_2.0
diff --git a/ld/testsuite/ld-elf/pr13195.t b/ld/testsuite/ld-elf/pr13195.t
new file mode 100644
index 0000000..2b82842
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr13195.t
@@ -0,0 +1,6 @@
+VERS_2.0 {
+global:
+  foo;
+local:
+  *;
+};