[binutils-gdb] ld: Keep PREINIT_ARRAY/INIT_ARRAY/FINI_ARRAY sections for -r --gc-sections

[H.J.Lu <hjl at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=8b6f4cd34fdde524ea035c65f7d48aaa3fb449b5

commit 8b6f4cd34fdde524ea035c65f7d48aaa3fb449b5
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Thu Jan 11 09:42:12 2018 -0800

    ld: Keep PREINIT_ARRAY/INIT_ARRAY/FINI_ARRAY sections for -r --gc-sections
    
    We must keep all PREINIT_ARRAY, INIT_ARRAY as well as FINI_ARRAY sections
    for ld -r --gc-sections.
    
    bfd/
    
    	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-sections.
    
    ld/
    
    	PR ld/22677
    	* scripttempl/elf.sc (PREINIT_ARRAY): New.
    	Don't add .preinit_array for ld -r.
    	* testsuite/ld-elf/pr22677.d: New file.
    	* testsuite/ld-elf/pr22677.s: Likewise.

Diff:
---
 bfd/ChangeLog                 |  6 ++++++
 bfd/elflink.c                 | 10 +++++++++-
 ld/ChangeLog                  |  8 ++++++++
 ld/scripttempl/elf.sc         | 13 +++++++------
 ld/testsuite/ld-elf/pr22677.d | 18 ++++++++++++++++++
 ld/testsuite/ld-elf/pr22677.s | 16 ++++++++++++++++
 6 files changed, 64 insertions(+), 7 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index a174a4c..8f2feae 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,9 @@
+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.
+
 2017-09-27  Kuan-Lin Chen  <kuanlinchentw@gmail.com>
 
 	PR 22662
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 15d9c7e..4c92a04 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -13428,11 +13428,19 @@ bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
 
       /* Start at sections marked with SEC_KEEP (ref _bfd_elf_gc_keep).
 	 Also treat note sections as a root, if the section is not part
-	 of a group.  */
+	 of a group.  We must keep all PREINIT_ARRAY, INIT_ARRAY as
+	 well as FINI_ARRAY sections for ld -r.  */
       for (o = sub->sections; o != NULL; o = o->next)
 	if (!o->gc_mark
 	    && (o->flags & SEC_EXCLUDE) == 0
 	    && ((o->flags & SEC_KEEP) != 0
+		|| (bfd_link_relocatable (info)
+		    && ((elf_section_data (o)->this_hdr.sh_type
+			 == SHT_PREINIT_ARRAY)
+			|| (elf_section_data (o)->this_hdr.sh_type
+			    == SHT_INIT_ARRAY)
+			|| (elf_section_data (o)->this_hdr.sh_type
+			    == SHT_FINI_ARRAY)))
 		|| (elf_section_data (o)->this_hdr.sh_type == SHT_NOTE
 		    && elf_next_in_group (o) == NULL )))
 	  {
diff --git a/ld/ChangeLog b/ld/ChangeLog
index 83545d5..34fdb1f 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,11 @@
+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.
+	* testsuite/ld-elf/pr22677.d: New file.
+	* testsuite/ld-elf/pr22677.s: Likewise.
+
 2018-01-11  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* ldexp.h (union etree_union): Remove defsym field.
diff --git a/ld/scripttempl/elf.sc b/ld/scripttempl/elf.sc
index 3de86b0..139773d 100644
--- a/ld/scripttempl/elf.sc
+++ b/ld/scripttempl/elf.sc
@@ -245,6 +245,12 @@ test "${LARGE_SECTIONS}" = "yes" && LARGE_SECTIONS="
     *(.ldata${RELOCATING+ .ldata.* .gnu.linkonce.l.*})
     ${RELOCATING+. = ALIGN(. != 0 ? ${ALIGNMENT} : 1);}
   }"
+PREINIT_ARRAY=".preinit_array   ${RELOCATING-0} :
+  {
+    ${RELOCATING+${CREATE_SHLIB-PROVIDE_HIDDEN (${USER_LABEL_PREFIX}__preinit_array_start = .);}}
+    KEEP (*(.preinit_array))
+    ${RELOCATING+${CREATE_SHLIB-PROVIDE_HIDDEN (${USER_LABEL_PREFIX}__preinit_array_end = .);}}
+  }"
 if test "${ENABLE_INITFINI_ARRAY}" = "yes"; then
   SORT_INIT_ARRAY="KEEP (*(SORT_BY_INIT_PRIORITY(.init_array.*) SORT_BY_INIT_PRIORITY(.ctors.*)))"
   SORT_FINI_ARRAY="KEEP (*(SORT_BY_INIT_PRIORITY(.fini_array.*) SORT_BY_INIT_PRIORITY(.dtors.*)))"
@@ -568,12 +574,7 @@ cat <<EOF
   .tdata	${RELOCATING-0} : { *(.tdata${RELOCATING+ .tdata.* .gnu.linkonce.td.*}) }
   .tbss		${RELOCATING-0} : { *(.tbss${RELOCATING+ .tbss.* .gnu.linkonce.tb.*})${RELOCATING+ *(.tcommon)} }
 
-  .preinit_array   ${RELOCATING-0} :
-  {
-    ${RELOCATING+${CREATE_SHLIB-PROVIDE_HIDDEN (${USER_LABEL_PREFIX}__preinit_array_start = .);}}
-    KEEP (*(.preinit_array))
-    ${RELOCATING+${CREATE_SHLIB-PROVIDE_HIDDEN (${USER_LABEL_PREFIX}__preinit_array_end = .);}}
-  }
+  ${RELOCATING+${PREINIT_ARRAY}}
   ${RELOCATING+${INIT_ARRAY}}
   ${RELOCATING+${FINI_ARRAY}}
   ${SMALL_DATA_CTOR-${RELOCATING+${CTOR}}}
diff --git a/ld/testsuite/ld-elf/pr22677.d b/ld/testsuite/ld-elf/pr22677.d
new file mode 100644
index 0000000..0d4ddf6
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr22677.d
@@ -0,0 +1,18 @@
+#ld: -r  --gc-sections -u foo
+#readelf: -S --wide
+#notarget: d30v-*-* dlx-*-* i960-*-* pj*-*-* pru-*-*
+#notarget: alpha-*-* hppa64-*-* i370-*-* i860-*-* ia64-*-* mep-*-* mn10200-*-*
+#xfail: cr16-*-* crx-*-* msp430-*-*
+# msp430 puts the init_array and fini_array inside the .rodata section.
+# generic linker targets don't support --gc-sections, nor do a bunch of
+# others.
+# cr16 and crx use non-standard scripts with memory regions, which don't
+# play well with unique group sections under ld -r.
+
+#...
+  \[[ 0-9]+\] \.preinit_array\.01000[ \t]+PREINIT_ARRAY[ \t0-9a-f]+WA?.*
+#...
+  \[[ 0-9]+\] \.init_array\.01000[ \t]+INIT_ARRAY[ \t0-9a-f]+WA?.*
+#...
+  \[[ 0-9]+\] \.fini_array\.01000[ \t]+FINI_ARRAY[ \t0-9a-f]+WA?.*
+#pass
diff --git a/ld/testsuite/ld-elf/pr22677.s b/ld/testsuite/ld-elf/pr22677.s
new file mode 100644
index 0000000..16f8bc3
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr22677.s
@@ -0,0 +1,16 @@
+	.section .preinit_array.01000,"aw",%preinit_array
+	.p2align 2
+	.word 0
+
+	.section .init_array.01000,"aw",%init_array
+	.p2align 2
+	.word 0
+
+	.section .fini_array.01000,"aw",%fini_array
+	.p2align 2
+	.word 0
+
+	.text
+	.globl foo
+foo:
+	.word 0