Ignore dynamic references on forced local symbols

We should ignore dynamic references on forced local symbols during
garbage collection since they can never be referenced dynamically.

bfd/

	PR ld/22649
	* elflink.c (bfd_elf_gc_mark_dynamic_ref_symbol): Ignore dynamic
	references on forced local symbols.

ld/

	PR ld/22649
	* testsuite/ld-elf/pr22649-1.s: New file.
	* testsuite/ld-elf/pr22649-2a.s: Likewise.
	* testsuite/ld-elf/pr22649-2b.s: Likewise.
	* testsuite/ld-elf/pr22649.msg: Likewise.
	* testsuite/ld-elf/shared.exp: Run ld/22649 tests.

8 files changed, 81 insertions, 1 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 8f2feae..5ceb5a0 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,5 +1,11 @@
 2018-01-11  H.J. Lu  <hongjiu.lu@intel.com>
 
+	PR ld/22649
+	* elflink.c (bfd_elf_gc_mark_dynamic_ref_symbol): Ignore dynamic
+	references on forced local symbols.
+
+2018-01-11  H.J. Lu  <hongjiu.lu@intel.com>
+
 	PR ld/22677
 	* elflink.c (bfd_elf_gc_sections): Keep all PREINIT_ARRAY,
 	INIT_ARRAY as well as FINI_ARRAY sections for ld -r --gc-section.
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 4c92a04..e3751fa 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -13277,7 +13277,7 @@ bfd_elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h, void *inf)
 
   if ((h->root.type == bfd_link_hash_defined
        || h->root.type == bfd_link_hash_defweak)
-      && (h->ref_dynamic
+      && ((h->ref_dynamic && !h->forced_local)
 	  || ((h->def_regular || ELF_COMMON_DEF_P (h))
 	      && ELF_ST_VISIBILITY (h->other) != STV_INTERNAL
 	      && ELF_ST_VISIBILITY (h->other) != STV_HIDDEN
diff --git a/ld/ChangeLog b/ld/ChangeLog
index 34fdb1f..977d779 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,5 +1,14 @@
 2018-01-11  H.J. Lu  <hongjiu.lu@intel.com>
 
+	PR ld/22649
+	* testsuite/ld-elf/pr22649-1.s: New file.
+	* testsuite/ld-elf/pr22649-2a.s: Likewise.
+	* testsuite/ld-elf/pr22649-2b.s: Likewise.
+	* testsuite/ld-elf/pr22649.msg: Likewise.
+	* testsuite/ld-elf/shared.exp: Run ld/22649 tests.
+
+2018-01-11  H.J. Lu  <hongjiu.lu@intel.com>
+
 	PR ld/22677
 	* scripttempl/elf.sc (PREINIT_ARRAY): New.
 	Don't add .preinit_array for ld -r.
diff --git a/ld/testsuite/ld-elf/pr22649-1.s b/ld/testsuite/ld-elf/pr22649-1.s
new file mode 100644
index 0000000..9a7da7e
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr22649-1.s
@@ -0,0 +1,4 @@
+	.data
+	.globl foo
+foo:
+	.dc.a bar
diff --git a/ld/testsuite/ld-elf/pr22649-2a.s b/ld/testsuite/ld-elf/pr22649-2a.s
new file mode 100644
index 0000000..b5908b0
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr22649-2a.s
@@ -0,0 +1,8 @@
+	.data
+	.hidden foo
+	.hidden bar
+	.globl foo
+	.globl bar
+foo:
+bar:
+	.dc.a foo
diff --git a/ld/testsuite/ld-elf/pr22649-2b.s b/ld/testsuite/ld-elf/pr22649-2b.s
new file mode 100644
index 0000000..999686c
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr22649-2b.s
@@ -0,0 +1,7 @@
+	.data
+	.hidden foo
+	.globl foo
+	.globl bar
+foo:
+bar:
+	.dc.a foo
diff --git a/ld/testsuite/ld-elf/pr22649.msg b/ld/testsuite/ld-elf/pr22649.msg
new file mode 100644
index 0000000..b4e45bd
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr22649.msg
@@ -0,0 +1 @@
+.*: Removing unused section '\.data' in file 'tmpdir/pr22649-2.*\.o'
diff --git a/ld/testsuite/ld-elf/shared.exp b/ld/testsuite/ld-elf/shared.exp
index 0c54568..95bac37 100644
--- a/ld/testsuite/ld-elf/shared.exp
+++ b/ld/testsuite/ld-elf/shared.exp
@@ -81,6 +81,51 @@ run_ld_link_tests [list \
 	{} \
 	"pr22471" \
     ] \
+    [list \
+	"Build pr22649-1.so" \
+	"$LFLAGS -shared" \
+	"" \
+	"$AFLAGS_PIC" \
+	{pr22649-1.s} \
+	{} \
+	"pr22649-1.so" \
+    ] \
+    [list \
+	"Build pr22649-2a.so" \
+	"$LFLAGS -shared -gc-sections -print-gc-sections" \
+	"" \
+	"$AFLAGS_PIC" \
+	{pr22649-2a.s} \
+	{{ld pr22649.msg}} \
+	"pr22649-2a.so" \
+    ] \
+    [list \
+	"Build pr22649-2b.so" \
+	"$LFLAGS -shared -gc-sections -print-gc-sections" \
+	"tmpdir/pr22649-1.so" \
+	"$AFLAGS_PIC" \
+	{pr22649-2a.s} \
+	{{ld pr22649.msg}} \
+	"pr22649-2b.so" \
+    ] \
+    [list \
+	"Build pr22649-2c.so" \
+	"$LFLAGS -shared -gc-sections -print-gc-sections" \
+	"" \
+	"$AFLAGS_PIC" \
+	{pr22649-2b.s} \
+	{} \
+	"pr22649-2b.so" \
+    ] \
+    [list \
+	"Build pr22649-2d.so" \
+	"$LFLAGS -shared -gc-sections -print-gc-sections" \
+	"tmpdir/pr22649-1.so" \
+	"$AFLAGS_PIC" \
+	{pr22649-2b.s} \
+	{} \
+	"pr22649-2b.so" \
+    ] \
 ]
 
 run_ld_link_tests [list \