ELF: Don't generate unused section symbols

For ELF targets, section symbols are required only for relocations.
With -ffunction-sections -fdata-sections, there can be many unused
section symbols.  Sizes of libstdc++.a on Linux/x86-64 in GCC 11 are

With unused section symbols   : 39411698 bytes
Without unused section symbols: 39227002 bytes

The unused section symbols in libstdc++.a occupy more than 180 KB.

Add BSF_SECTION_SYM_USED to indicate if a section symbol should be
included in the symbol table.  The BSF_SECTION_SYM_USED should be set
if the section symbol is used for relocation or the section symbol is
always included in the symbol table.

Add keep_unused_section_symbols to bfd_target to indicate if unused
section symbols should be kept.  If TARGET_KEEP_UNUSED_SECTION_SYMBOLS
is defined as FALSE, unused ection symbols will be removed.

Tested on Linux/x86.  Other ELF backends need to:

1. Define TARGET_KEEP_UNUSED_SECTION_SYMBOLS to FALSE.
2. Mark used section symbols in assembler backend.
3. Remove unused section symbols from expected assembler and linker
outputs.

bfd/

	PR 27109
	* aix386-core.c (core_aix386_vec): Initialize
	keep_unused_section_symbol to TARGET_KEEP_UNUSED_SECTION_SYMBOLS.
	* aout-target.h (MY (vec)): Likewise.
	* binary.c (binary_vec): Likewise.
	* cisco-core.c (core_cisco_be_vec): Likewise.
	(core_cisco_le_vec): Likewise.
	* coff-alpha.c (alpha_ecoff_le_vec): Likewise.
	* coff-i386.c (TARGET_SYM): Likewise.
	(TARGET_SYM_BIG): Likewise.
	* coff-ia64.c (TARGET_SYM): Likewise.
	* coff-mips.c (mips_ecoff_le_vec): Likewise.
	(mips_ecoff_be_vec): Likewise.
	(mips_ecoff_bele_vec): Likewise.
	* coff-rs6000.c (rs6000_xcoff_vec): Likewise.
	(powerpc_xcoff_vec): Likewise.
	* coff-sh.c (sh_coff_small_vec): Likewise.
	(sh_coff_small_le_vec): Likewise.
	* coff-tic30.c (tic30_coff_vec): Likewise.
	* coff-tic54x.c (tic54x_coff0_vec): Likewise.
	(tic54x_coff0_beh_vec): Likewise.
	(tic54x_coff1_vec): Likewise.
	(tic54x_coff1_beh_vec): Likewise.
	(tic54x_coff2_vec): Likewise.
	(tic54x_coff2_beh_vec): Likewise.
	* coff-x86_64.c (TARGET_SYM): Likewise.
	(TARGET_SYM_BIG): Likewise.
	* coff64-rs6000.c (rs6000_xcoff64_vec): Likewise.
	(rs6000_xcoff64_aix_vec): Likewise.
	* coffcode.h (CREATE_BIG_COFF_TARGET_VEC): Likewise.
	(CREATE_BIGHDR_COFF_TARGET_VEC): Likewise.
	(CREATE_LITTLE_COFF_TARGET_VEC): Likewise.
	* elfxx-target.h (TARGET_BIG_SYM): Likewise.
	(TARGET_LITTLE_SYM): Likewise.
	* hppabsd-core.c (core_hppabsd_vec): Likewise.
	* hpux-core.c (core_hpux_vec): Likewise.
	* i386msdos.c (i386_msdos_vec): Likewise.
	* ihex.c (ihex_vec): Likewise.
	* irix-core.c (core_irix_vec): Likewise.
	* mach-o-target.c (TARGET_NAME): Likewise.
	* mmo.c (mmix_mmo_vec): Likewise.
	* netbsd-core.c (core_netbsd_vec): Likewise.
	* osf-core.c (core_osf_vec): Likewise.
	* pdp11.c (MY (vec)): Likewise.
	* pef.c (pef_vec): Likewise.
	(pef_xlib_vec): Likewise.
	* plugin.c (plugin_vec): Likewise.
	* ppcboot.c (powerpc_boot_vec): Likewise.
	* ptrace-core.c (core_ptrace_vec): Likewise.
	* sco5-core.c (core_sco5_vec): Likewise.
	* som.c (hppa_som_vec): Likewise.
	* srec.c (srec_vec): Likewise.
	(symbolsrec_vec): Likewise.
	* tekhex.c (tekhex_vec): Likewise.
	* trad-core.c (core_trad_vec): Likewise.
	* verilog.c (verilog_vec): Likewise.
	* vms-alpha.c (alpha_vms_vec): Likewise.
	* vms-lib.c (alpha_vms_lib_txt_vec): Likewise.
	* wasm-module.c (wasm_vec): Likewise.
	* xsym.c (sym_vec): Likewise.
	* elf.c (ignore_section_sym): Return TRUE if BSF_SECTION_SYM_USED
	isn't set.
	(elf_map_symbols): Don't include ignored section symbols.
	* elfcode.h (elf_slurp_symbol_table): Also set
	BSF_SECTION_SYM_USED on STT_SECTION symbols.
	* elflink.c (bfd_elf_final_link): Generated section symbols only
	when emitting relocations or reqired.
	* elfxx-x86.h (TARGET_KEEP_UNUSED_SECTION_SYMBOLS): New.
	* syms.c (BSF_SECTION_SYM_USED): New.
	* targets.c (TARGET_KEEP_UNUSED_SECTION_SYMBOLS): New.
	(bfd_target): Add keep_unused_section_symbols.
	(bfd_keep_unused_section_symbols): New.
	* bfd-in2.h: Regenerated.

binutils/

	PR 27109
	* objcopy.c (copy_object): Handle section symbols for
	non-relocatable inputs.
	* testsuite/binutils-all/readelf.exp (readelf_test): Check
	is_elf_unused_section_symbols.
	* testsuite/binutils-all/readelf.s-64: Updated.
	* testsuite/binutils-all/readelf.ss: Likewise.
	* testsuite/binutils-all/readelf.ss-64: Likewise.
	* testsuite/binutils-all/readelf.s-64-unused: New file.
	* testsuite/binutils-all/readelf.ss-64-unused: Likewise.
	* testsuite/binutils-all/readelf.ss-unused: Likewise.
	* testsuite/lib/binutils-common.exp
	(is_elf_unused_section_symbols): New proc.

gas/ChangeLog:

	PR 27109
	* read.c (s_reloc): Call symbol_mark_used_in_reloc on the
	section symbol.
	* subsegs.c (subseg_set_rest): Set BSF_SECTION_SYM_USED if needed.
	* write.c (adjust_reloc_syms): Call symbol_mark_used_in_reloc
	on the section symbol.
	(set_symtab): Don't generate unused section symbols.
	(maybe_generate_build_notes): Call symbol_mark_used_in_reloc
	on the section symbol.
	* config/obj-elf.c (elf_adjust_symtab): Call
	symbol_mark_used_in_reloc on the group signature symbol.
	* testsuite/gas/cfi/cfi-label.d: Remove unused section symbols
	from expected output.
	* testsuite/gas/elf/elf.exp (run_elf_list_test): Check
	is_elf_unused_section_symbols.
	* testsuite/gas/elf/section2.e: Updated.
	* testsuite/gas/elf/section2.e-unused: New file.
	* testsuite/gas/elf/symver.d: Remove unused section symbols.
	* testsuite/gas/i386/ilp32/elf/symver.d: Likewise.
	* testsuite/gas/i386/ilp32/x86-64-size-1.d: Likewise.
	* testsuite/gas/i386/ilp32/x86-64-size-3.d: Likewise.
	* testsuite/gas/i386/ilp32/x86-64-size-5.d: Likewise.
	* testsuite/gas/i386/ilp32/x86-64-unwind.d: Likewise.
	* testsuite/gas/i386/size-1.d: Likewise.
	* testsuite/gas/i386/size-3.d: Likewise.
	* testsuite/gas/i386/svr4.d: Likewise.
	* testsuite/gas/i386/x86-64-size-1.d: Likewise.
	* testsuite/gas/i386/x86-64-size-3.d: Likewise.
	* testsuite/gas/i386/x86-64-size-5.d: Likewise.
	* testsuite/gas/i386/x86-64-unwind.d: Likewise.

ld/

	PR 27109
	* testsuite/ld-elf/export-class.sd: Adjust the expected output.
	* testsuite/ld-elf/loadaddr3b.d: Likewise.
	* testsuite/ld-i386/ibt-plt-1.d: Likewise.
	* testsuite/ld-i386/ibt-plt-2a.d: Likewise.
	* testsuite/ld-i386/ibt-plt-2c.d: Likewise.
	* testsuite/ld-i386/ibt-plt-3a.d: Likewise.
	* testsuite/ld-i386/ibt-plt-3c.d: Likewise.
	* testsuite/ld-i386/pr19636-1d.d: Likewise.
	* testsuite/ld-i386/pr19636-1l.d: Likewise.
	* testsuite/ld-i386/pr19636-2c.d: Likewise.
	* testsuite/ld-ifunc/ifunc-2-i386-now.d: Likewise.
	* testsuite/ld-ifunc/ifunc-2-local-i386-now.d: Likewise.
	* testsuite/ld-ifunc/ifunc-2-local-x86-64-now.d: Likewise.
	* testsuite/ld-ifunc/ifunc-2-x86-64-now.d: Likewise.
	* testsuite/ld-ifunc/ifunc-21-x86-64.d: Likewise.
	* testsuite/ld-ifunc/ifunc-22-x86-64.d: Likewise.
	* testsuite/ld-ifunc/pr17154-i386-now.d: Likewise.
	* testsuite/ld-ifunc/pr17154-i386.d: Likewise.
	* testsuite/ld-ifunc/pr17154-x86-64-now.d: Likewise.
	* testsuite/ld-ifunc/pr17154-x86-64.d: Likewise.
	* testsuite/ld-x86-64/bnd-branch-1-now.d: Likewise.
	* testsuite/ld-x86-64/bnd-ifunc-1-now.d: Likewise.
	* testsuite/ld-x86-64/bnd-ifunc-2-now.d: Likewise.
	* testsuite/ld-x86-64/bnd-ifunc-2.d: Likewise.
	* testsuite/ld-x86-64/bnd-plt-1-now.d: Likewise.
	* testsuite/ld-x86-64/bnd-plt-1.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-1-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-1.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2a-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2a.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2c-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2c.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3a-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3a.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3c-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3c.d: Likewise.
	* testsuite/ld-x86-64/pr19609-4e.d: Likewise.
	* testsuite/ld-x86-64/pr19609-6a.d: Likewise.
	* testsuite/ld-x86-64/pr19609-6b.d: Likewise.
	* testsuite/ld-x86-64/pr19609-7b.d: Likewise.
	* testsuite/ld-x86-64/pr19609-7d.d: Likewise.
	* testsuite/ld-x86-64/pr19636-2l.d: Likewise.
	* testsuite/ld-x86-64/pr20253-1d.d: Likewise.
	* testsuite/ld-x86-64/pr20253-1h.d: Likewise.
	* testsuite/ld-x86-64/pr21038b-now.d: Likewise.
	* testsuite/ld-x86-64/pr21038b.d: Likewise.
	* testsuite/ld-x86-64/pr21038c-now.d: Likewise.
	* testsuite/ld-x86-64/pr21038c.d: Likewise.
	* testsuite/ld-x86-64/pr23854.d: Likewise.
	* testsuite/ld-x86-64/pr25416-3.d: Likewise.
	* testsuite/ld-x86-64/pr25416-4.d: Likewise.
	* testsuite/ld-i386/plt-pic.pd: Likewise.
	* testsuite/ld-i386/plt-pic2.dd: Likewise.
	* testsuite/ld-i386/plt.pd: Likewise.
	* testsuite/ld-i386/plt2.dd: Likewise.
	* testsuite/ld-i386/tlsbin.rd: Likewise.
	* testsuite/ld-i386/tlsbin2.rd: Likewise.
	* testsuite/ld-i386/tlsbindesc.rd: Likewise.
	* testsuite/ld-i386/tlsdesc.rd: Likewise.
	* testsuite/ld-i386/tlsgdesc.rd: Likewise.
	* testsuite/ld-i386/tlsnopic.rd: Likewise.
	* testsuite/ld-i386/tlspic.rd: Likewise.
	* testsuite/ld-i386/tlspic2.rd: Likewise.
	* testsuite/ld-x86-64/mpx3.dd: Likewise.
	* testsuite/ld-x86-64/mpx3n.dd: Likewise.
	* testsuite/ld-x86-64/mpx4.dd: Likewise.
	* testsuite/ld-x86-64/mpx4n.dd: Likewise.
	* testsuite/ld-x86-64/pe-x86-64-1.od: Likewise.
	* testsuite/ld-x86-64/pe-x86-64-2.od: Likewise.
	* testsuite/ld-x86-64/pe-x86-64-3.od: Likewise.
	* testsuite/ld-x86-64/pe-x86-64-4.od: Likewise.
	* testsuite/ld-x86-64/plt.pd: Likewise.
	* testsuite/ld-x86-64/plt2.dd: Likewise.
	* testsuite/ld-x86-64/tlsbin.rd: Likewise.
	* testsuite/ld-x86-64/tlsbin2.rd: Likewise.
	* testsuite/ld-x86-64/tlsbindesc.rd: Likewise.
	* testsuite/ld-x86-64/tlsdesc.rd: Likewise.
	* testsuite/ld-x86-64/tlsgdesc.rd: Likewise.
	* testsuite/ld-x86-64/tlspic.rd: Likewise.
	* testsuite/ld-x86-64/tlspic2.rd: Likewise.
	* testsuite/ld-elf/sec64k.exp: Check
	is_elf_unused_section_symbols.

48 files changed, 245 insertions, 36 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index ec3ab0a..69313e1 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,79 @@
+2021-01-07  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR 27109
+	* aix386-core.c (core_aix386_vec): Initialize
+	keep_unused_section_symbol to TARGET_KEEP_UNUSED_SECTION_SYMBOLS.
+	* aout-target.h (MY (vec)): Likewise.
+	* binary.c (binary_vec): Likewise.
+	* cisco-core.c (core_cisco_be_vec): Likewise.
+	(core_cisco_le_vec): Likewise.
+	* coff-alpha.c (alpha_ecoff_le_vec): Likewise.
+	* coff-i386.c (TARGET_SYM): Likewise.
+	(TARGET_SYM_BIG): Likewise.
+	* coff-ia64.c (TARGET_SYM): Likewise.
+	* coff-mips.c (mips_ecoff_le_vec): Likewise.
+	(mips_ecoff_be_vec): Likewise.
+	(mips_ecoff_bele_vec): Likewise.
+	* coff-rs6000.c (rs6000_xcoff_vec): Likewise.
+	(powerpc_xcoff_vec): Likewise.
+	* coff-sh.c (sh_coff_small_vec): Likewise.
+	(sh_coff_small_le_vec): Likewise.
+	* coff-tic30.c (tic30_coff_vec): Likewise.
+	* coff-tic54x.c (tic54x_coff0_vec): Likewise.
+	(tic54x_coff0_beh_vec): Likewise.
+	(tic54x_coff1_vec): Likewise.
+	(tic54x_coff1_beh_vec): Likewise.
+	(tic54x_coff2_vec): Likewise.
+	(tic54x_coff2_beh_vec): Likewise.
+	* coff-x86_64.c (TARGET_SYM): Likewise.
+	(TARGET_SYM_BIG): Likewise.
+	* coff64-rs6000.c (rs6000_xcoff64_vec): Likewise.
+	(rs6000_xcoff64_aix_vec): Likewise.
+	* coffcode.h (CREATE_BIG_COFF_TARGET_VEC): Likewise.
+	(CREATE_BIGHDR_COFF_TARGET_VEC): Likewise.
+	(CREATE_LITTLE_COFF_TARGET_VEC): Likewise.
+	* elfxx-target.h (TARGET_BIG_SYM): Likewise.
+	(TARGET_LITTLE_SYM): Likewise.
+	* hppabsd-core.c (core_hppabsd_vec): Likewise.
+	* hpux-core.c (core_hpux_vec): Likewise.
+	* i386msdos.c (i386_msdos_vec): Likewise.
+	* ihex.c (ihex_vec): Likewise.
+	* irix-core.c (core_irix_vec): Likewise.
+	* mach-o-target.c (TARGET_NAME): Likewise.
+	* mmo.c (mmix_mmo_vec): Likewise.
+	* netbsd-core.c (core_netbsd_vec): Likewise.
+	* osf-core.c (core_osf_vec): Likewise.
+	* pdp11.c (MY (vec)): Likewise.
+	* pef.c (pef_vec): Likewise.
+	(pef_xlib_vec): Likewise.
+	* plugin.c (plugin_vec): Likewise.
+	* ppcboot.c (powerpc_boot_vec): Likewise.
+	* ptrace-core.c (core_ptrace_vec): Likewise.
+	* sco5-core.c (core_sco5_vec): Likewise.
+	* som.c (hppa_som_vec): Likewise.
+	* srec.c (srec_vec): Likewise.
+	(symbolsrec_vec): Likewise.
+	* tekhex.c (tekhex_vec): Likewise.
+	* trad-core.c (core_trad_vec): Likewise.
+	* verilog.c (verilog_vec): Likewise.
+	* vms-alpha.c (alpha_vms_vec): Likewise.
+	* vms-lib.c (alpha_vms_lib_txt_vec): Likewise.
+	* wasm-module.c (wasm_vec): Likewise.
+	* xsym.c (sym_vec): Likewise.
+	* elf.c (ignore_section_sym): Return TRUE if BSF_SECTION_SYM_USED
+	isn't set.
+	(elf_map_symbols): Don't include ignored section symbols.
+	* elfcode.h (elf_slurp_symbol_table): Also set
+	BSF_SECTION_SYM_USED on STT_SECTION symbols.
+	* elflink.c (bfd_elf_final_link): Generated section symbols only
+	when emitting relocations or reqired.
+	* elfxx-x86.h (TARGET_KEEP_UNUSED_SECTION_SYMBOLS): New.
+	* syms.c (BSF_SECTION_SYM_USED): New.
+	* targets.c (TARGET_KEEP_UNUSED_SECTION_SYMBOLS): New.
+	(bfd_target): Add keep_unused_section_symbols.
+	(bfd_keep_unused_section_symbols): New.
+	* bfd-in2.h: Regenerated.
+
 2021-01-07  Nick Clifton  <nickc@redhat.com>
 
 	PR 25713
diff --git a/bfd/aix386-core.c b/bfd/aix386-core.c
index d641b81..68cd642 100644
--- a/bfd/aix386-core.c
+++ b/bfd/aix386-core.c
@@ -239,6 +239,7 @@ const bfd_target core_aix386_vec =
   ' ',				/* ar_pad_char */
   16,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   NO_GET64, NO_GETS64, NO_PUT64,
   NO_GET, NO_GETS, NO_PUT,
   NO_GET, NO_GETS, NO_PUT,	/* data */
diff --git a/bfd/aout-target.h b/bfd/aout-target.h
index 8c27bb1..92fc3ed 100644
--- a/bfd/aout-target.h
+++ b/bfd/aout-target.h
@@ -660,6 +660,7 @@ const bfd_target MY (vec) =
   AR_PAD_CHAR,			/* AR_pad_char.  */
   15,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 #ifdef TARGET_IS_BIG_ENDIAN_P
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
      bfd_getb32, bfd_getb_signed_32, bfd_putb32,
diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h
index 43ead18..7eff85b 100644
--- a/bfd/bfd-in2.h
+++ b/bfd/bfd-in2.h
@@ -6416,6 +6416,9 @@ typedef struct bfd_symbol
      with this name and type in use.  BSF_OBJECT must also be set.  */
 #define BSF_GNU_UNIQUE          (1 << 23)
 
+  /* This section symbol should be included in the symbol table.  */
+#define BSF_SECTION_SYM_USED    (1 << 24)
+
   flagword flags;
 
   /* A pointer to the section to which this symbol is
@@ -7291,6 +7294,11 @@ bfd_boolean generic_core_file_matches_executable_p
    (bfd_assert (__FILE__,__LINE__), NULL))
 #endif
 
+/* Defined to TRUE if unused section symbol should be kept.  */
+#ifndef TARGET_KEEP_UNUSED_SECTION_SYMBOLS
+#define TARGET_KEEP_UNUSED_SECTION_SYMBOLS TRUE
+#endif
+
 enum bfd_flavour
 {
   /* N.B. Update bfd_flavour_name if you change this.  */
@@ -7364,6 +7372,9 @@ typedef struct bfd_target
      possible targets when more than one target matches.  */
   unsigned char match_priority;
 
+ /* TRUE if unused section symbols should be kept.  */
+  bfd_boolean keep_unused_section_symbols;
+
   /* Entries for byte swapping for data. These are different from the
      other entry points, since they don't take a BFD as the first argument.
      Certain other handlers could do the same.  */
@@ -7794,6 +7805,12 @@ bfd_asymbol_flavour (const asymbol *sy)
   return sy->the_bfd->xvec->flavour;
 }
 
+static inline bfd_boolean
+bfd_keep_unused_section_symbols (const bfd *abfd)
+{
+  return abfd->xvec->keep_unused_section_symbols;
+}
+
 bfd_boolean bfd_set_default_target (const char *name);
 
 const bfd_target *bfd_find_target (const char *target_name, bfd *abfd);
diff --git a/bfd/binary.c b/bfd/binary.c
index db1bec0..942c66b 100644
--- a/bfd/binary.c
+++ b/bfd/binary.c
@@ -335,6 +335,7 @@ const bfd_target binary_vec =
   ' ',				/* ar_pad_char */
   16,				/* ar_max_namelen */
   255,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* data */
diff --git a/bfd/cisco-core.c b/bfd/cisco-core.c
index 1b77829..c0e68ad 100644
--- a/bfd/cisco-core.c
+++ b/bfd/cisco-core.c
@@ -329,6 +329,7 @@ const bfd_target core_cisco_be_vec =
   ' ',				/* ar_pad_char */
   16,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
@@ -384,6 +385,7 @@ const bfd_target core_cisco_le_vec =
   ' ',				/* ar_pad_char */
   16,				/* ar_max_namelen */
   0,				/* match_priority */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
   bfd_getl32, bfd_getl_signed_32, bfd_putl32,
   bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
diff --git a/bfd/coff-alpha.c b/bfd/coff-alpha.c
index 50b2f97..db26587 100644
--- a/bfd/coff-alpha.c
+++ b/bfd/coff-alpha.c
@@ -2427,6 +2427,7 @@ const bfd_target alpha_ecoff_le_vec =
   ' ',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
      bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
diff --git a/bfd/coff-i386.c b/bfd/coff-i386.c
index 5048df9..e025195 100644
--- a/bfd/coff-i386.c
+++ b/bfd/coff-i386.c
@@ -651,6 +651,7 @@ const bfd_target
   '/',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
@@ -729,6 +730,7 @@ const bfd_target
   '/',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
@@ -772,4 +774,4 @@ const bfd_target
 
   &bigobj_swap_table
 };
-#endif
\ No newline at end of file
+#endif
diff --git a/bfd/coff-ia64.c b/bfd/coff-ia64.c
index 24a4a7c..887c7aa 100644
--- a/bfd/coff-ia64.c
+++ b/bfd/coff-ia64.c
@@ -170,6 +170,7 @@ const bfd_target
   '/',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
diff --git a/bfd/coff-mips.c b/bfd/coff-mips.c
index 38376b2..d20f4b4 100644
--- a/bfd/coff-mips.c
+++ b/bfd/coff-mips.c
@@ -1446,6 +1446,7 @@ const bfd_target mips_ecoff_le_vec =
   ' ',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
      bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
@@ -1504,6 +1505,7 @@ const bfd_target mips_ecoff_be_vec =
   ' ',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
      bfd_getb32, bfd_getb_signed_32, bfd_putb32,
      bfd_getb16, bfd_getb_signed_16, bfd_putb16,
@@ -1562,6 +1564,7 @@ const bfd_target mips_ecoff_bele_vec =
   ' ',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
      bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
diff --git a/bfd/coff-rs6000.c b/bfd/coff-rs6000.c
index a71791e..fbc1aed 100644
--- a/bfd/coff-rs6000.c
+++ b/bfd/coff-rs6000.c
@@ -4201,6 +4201,7 @@ const bfd_target rs6000_xcoff_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
     /* data */
     bfd_getb64,
@@ -4382,6 +4383,7 @@ const bfd_target powerpc_xcoff_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
     /* data */
     bfd_getb64,
diff --git a/bfd/coff-sh.c b/bfd/coff-sh.c
index 99541a7..04ef99b 100644
--- a/bfd/coff-sh.c
+++ b/bfd/coff-sh.c
@@ -3134,6 +3134,7 @@ const bfd_target sh_coff_small_vec =
   '/',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
@@ -3191,6 +3192,7 @@ const bfd_target sh_coff_small_le_vec =
   '/',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
   bfd_getl32, bfd_getl_signed_32, bfd_putl32,
   bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
diff --git a/bfd/coff-tic30.c b/bfd/coff-tic30.c
index f3e7df0..f4d3a13 100644
--- a/bfd/coff-tic30.c
+++ b/bfd/coff-tic30.c
@@ -192,6 +192,7 @@ const bfd_target tic30_coff_vec =
   '/',				/* ar_pad_char */
   15,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* data */
diff --git a/bfd/coff-tic54x.c b/bfd/coff-tic54x.c
index 914bb2a..3c18221 100644
--- a/bfd/coff-tic54x.c
+++ b/bfd/coff-tic54x.c
@@ -415,6 +415,7 @@ const bfd_target tic54x_coff0_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
     tic54x_getl32, tic54x_getl_signed_32, tic54x_putl32,
     bfd_getl16, bfd_getl_signed_16, bfd_putl16,	/* data */
@@ -472,6 +473,11 @@ const bfd_target tic54x_coff0_beh_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+#ifdef TARGET_KEEP_UNUSED_SECTION_SYMBOLS
+    TRUE,			/* keep unused section symbols.  */
+#else
+    FALSE,			/* keep unused section symbols.  */
+#endif
     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
     tic54x_getl32, tic54x_getl_signed_32, tic54x_putl32,
     bfd_getl16, bfd_getl_signed_16, bfd_putl16,	/* data */
@@ -530,6 +536,11 @@ const bfd_target tic54x_coff1_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+#ifdef TARGET_KEEP_UNUSED_SECTION_SYMBOLS
+    TRUE,			/* keep unused section symbols.  */
+#else
+    FALSE,			/* keep unused section symbols.  */
+#endif
     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
     tic54x_getl32, tic54x_getl_signed_32, tic54x_putl32,
     bfd_getl16, bfd_getl_signed_16, bfd_putl16,	/* data */
@@ -588,6 +599,11 @@ const bfd_target tic54x_coff1_beh_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+#ifdef TARGET_KEEP_UNUSED_SECTION_SYMBOLS
+    TRUE,			/* keep unused section symbols.  */
+#else
+    FALSE,			/* keep unused section symbols.  */
+#endif
     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
     tic54x_getl32, tic54x_getl_signed_32, tic54x_putl32,
     bfd_getl16, bfd_getl_signed_16, bfd_putl16,	/* data */
@@ -646,6 +662,11 @@ const bfd_target tic54x_coff2_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+#ifdef TARGET_KEEP_UNUSED_SECTION_SYMBOLS
+    TRUE,			/* keep unused section symbols.  */
+#else
+    FALSE,			/* keep unused section symbols.  */
+#endif
     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
     tic54x_getl32, tic54x_getl_signed_32, tic54x_putl32,
     bfd_getl16, bfd_getl_signed_16, bfd_putl16,	/* data */
@@ -704,6 +725,11 @@ const bfd_target tic54x_coff2_beh_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+#ifdef TARGET_KEEP_UNUSED_SECTION_SYMBOLS
+    TRUE,			/* keep unused section symbols.  */
+#else
+    FALSE,			/* keep unused section symbols.  */
+#endif
     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
     tic54x_getl32, tic54x_getl_signed_32, tic54x_putl32,
     bfd_getl16, bfd_getl_signed_16, bfd_putl16,	/* data */
diff --git a/bfd/coff-x86_64.c b/bfd/coff-x86_64.c
index 0279ce2..adab60c 100644
--- a/bfd/coff-x86_64.c
+++ b/bfd/coff-x86_64.c
@@ -782,6 +782,7 @@ const bfd_target
   '/',				/* Ar_pad_char.  */
   15,				/* Ar_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
@@ -854,6 +855,7 @@ const bfd_target
   '/',				/* Ar_pad_char.  */
   15,				/* Ar_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
      bfd_getl32, bfd_getl_signed_32, bfd_putl32,
diff --git a/bfd/coff64-rs6000.c b/bfd/coff64-rs6000.c
index a3b1702..9aa0304 100644
--- a/bfd/coff64-rs6000.c
+++ b/bfd/coff64-rs6000.c
@@ -2665,6 +2665,7 @@ const bfd_target rs6000_xcoff64_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
     /* data */
     bfd_getb64,
@@ -2928,6 +2929,7 @@ const bfd_target rs6000_xcoff64_aix_vec =
     '/',			/* ar_pad_char */
     15,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
     /* data */
     bfd_getb64,
diff --git a/bfd/coffcode.h b/bfd/coffcode.h
index 21820da..2fd699f 100644
--- a/bfd/coffcode.h
+++ b/bfd/coffcode.h
@@ -5820,6 +5820,7 @@ const bfd_target VAR =							\
   '/',				/* AR_pad_char.  */			\
   15,				/* AR_max_namelen.  */			\
   0,				/* match priority.  */			\
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */ \
 									\
   /* Data conversion functions.  */					\
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,				\
@@ -5881,6 +5882,7 @@ const bfd_target VAR =							\
   '/',				/* AR_pad_char.  */			\
   15,				/* AR_max_namelen.  */			\
   0,				/* match priority.  */			\
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */ \
 									\
   /* Data conversion functions.  */					\
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,				\
@@ -5942,6 +5944,7 @@ const bfd_target VAR =							\
   '/',				/* AR_pad_char.  */			\
   15,				/* AR_max_namelen.  */			\
   0,				/* match priority.  */			\
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */ \
 									\
   /* Data conversion functions.  */					\
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,				\
diff --git a/bfd/elf.c b/bfd/elf.c
index 3f4ccd2..ab19bdb 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -4061,6 +4061,10 @@ ignore_section_sym (bfd *abfd, asymbol *sym)
   if ((sym->flags & BSF_SECTION_SYM) == 0)
     return FALSE;
 
+  /* Ignore the section symbol if it isn't used.  */
+  if ((sym->flags & BSF_SECTION_SYM_USED) == 0)
+    return TRUE;
+
   if (sym->section == NULL)
     return TRUE;
 
@@ -4148,7 +4152,10 @@ elf_map_symbols (bfd *abfd, unsigned int *pnum_locals)
      at least in that case.  */
   for (asect = abfd->sections; asect; asect = asect->next)
     {
-      if (sect_syms[asect->index] == NULL)
+      asymbol *sym = asect->symbol;
+      /* Don't include ignored section symbols.  */
+      if (!ignore_section_sym (abfd, sym)
+	  && sect_syms[asect->index] == NULL)
 	{
 	  if (!sym_is_global (abfd, asect->symbol))
 	    num_locals++;
@@ -4170,6 +4177,7 @@ elf_map_symbols (bfd *abfd, unsigned int *pnum_locals)
 
       if (sym_is_global (abfd, sym))
 	i = num_locals + num_globals2++;
+      /* Don't include ignored section symbols.  */
       else if (!ignore_section_sym (abfd, sym))
 	i = num_locals2++;
       else
@@ -4179,9 +4187,10 @@ elf_map_symbols (bfd *abfd, unsigned int *pnum_locals)
     }
   for (asect = abfd->sections; asect; asect = asect->next)
     {
-      if (sect_syms[asect->index] == NULL)
+      asymbol *sym = asect->symbol;
+      if (!ignore_section_sym (abfd, sym)
+	  && sect_syms[asect->index] == NULL)
 	{
-	  asymbol *sym = asect->symbol;
 	  unsigned int i;
 
 	  sect_syms[asect->index] = sym;
diff --git a/bfd/elfcode.h b/bfd/elfcode.h
index b40fb4a..4e99fcc 100644
--- a/bfd/elfcode.h
+++ b/bfd/elfcode.h
@@ -1347,7 +1347,13 @@ elf_slurp_symbol_table (bfd *abfd, asymbol **symptrs, bfd_boolean dynamic)
 	  switch (ELF_ST_TYPE (isym->st_info))
 	    {
 	    case STT_SECTION:
-	      sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING;
+	      /* Mark the input section symbol as used since it may be
+	         used for relocation and section group.
+		 NB: BSF_SECTION_SYM_USED is ignored by linker and may
+		 be cleared by objcopy for non-relocatable inputs.  */
+	      sym->symbol.flags |= (BSF_SECTION_SYM
+				    | BSF_DEBUGGING
+				    | BSF_SECTION_SYM_USED);
 	      break;
 	    case STT_FILE:
 	      sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING;
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 4c54b1a..a7c952b 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -12527,9 +12527,6 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
 
   if (info->strip != strip_all || emit_relocs)
     {
-      bfd_boolean name_local_sections;
-      const char *name;
-
       file_ptr off = elf_next_file_pos (abfd);
 
       _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
@@ -12550,36 +12547,38 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
 				     bfd_und_section_ptr, NULL) != 1)
 	goto error_return;
 
-      /* Output a symbol for each section.  We output these even if we are
-	 discarding local symbols, since they are used for relocs.  These
-	 symbols usually have no names.  We store the index of each one in
-	 the index field of the section, so that we can find it again when
-	 outputting relocs.  */
+      /* Output a symbol for each section if asked or they are used for
+	 relocs.  These symbols usually have no names.  We store the
+	 index of each one in the index field of the section, so that
+	 we can find it again when outputting relocs.  */
 
-      name_local_sections
-	= (bed->elf_backend_name_local_section_symbols
-	   && bed->elf_backend_name_local_section_symbols (abfd));
+      if (bfd_keep_unused_section_symbols (abfd) || emit_relocs)
+	{
+	  bfd_boolean name_local_sections
+	    = (bed->elf_backend_name_local_section_symbols
+	       && bed->elf_backend_name_local_section_symbols (abfd));
+	  const char *name = NULL;
 
-      name = NULL;
-      elfsym.st_size = 0;
-      elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
-      elfsym.st_other = 0;
-      elfsym.st_value = 0;
-      elfsym.st_target_internal = 0;
-      for (i = 1; i < elf_numsections (abfd); i++)
-	{
-	  o = bfd_section_from_elf_index (abfd, i);
-	  if (o != NULL)
-	    {
-	      o->target_index = bfd_get_symcount (abfd);
-	      elfsym.st_shndx = i;
-	      if (!bfd_link_relocatable (info))
-		elfsym.st_value = o->vma;
-	      if (name_local_sections)
-		name = o->name;
-	      if (elf_link_output_symstrtab (&flinfo, name, &elfsym, o,
-					     NULL) != 1)
-		goto error_return;
+	  elfsym.st_size = 0;
+	  elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
+	  elfsym.st_other = 0;
+	  elfsym.st_value = 0;
+	  elfsym.st_target_internal = 0;
+	  for (i = 1; i < elf_numsections (abfd); i++)
+	    {
+	      o = bfd_section_from_elf_index (abfd, i);
+	      if (o != NULL)
+		{
+		  o->target_index = bfd_get_symcount (abfd);
+		  elfsym.st_shndx = i;
+		  if (!bfd_link_relocatable (info))
+		    elfsym.st_value = o->vma;
+		  if (name_local_sections)
+		    name = o->name;
+		  if (elf_link_output_symstrtab (&flinfo, name, &elfsym, o,
+						 NULL) != 1)
+		    goto error_return;
+		}
 	    }
 	}
     }
diff --git a/bfd/elfxx-target.h b/bfd/elfxx-target.h
index cae1fbf..c930b76 100644
--- a/bfd/elfxx-target.h
+++ b/bfd/elfxx-target.h
@@ -1007,6 +1007,9 @@ const bfd_target TARGET_BIG_SYM =
 
   elf_match_priority,
 
+  /* TRUE if unused section symbols should be kept.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS,
+
   /* Routines to byte-swap various sized integers from the data sections */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
@@ -1108,6 +1111,9 @@ const bfd_target TARGET_LITTLE_SYM =
 
   elf_match_priority,
 
+  /* TRUE if unused section symbols should be kept.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS,
+
   /* Routines to byte-swap various sized integers from the data sections */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
diff --git a/bfd/elfxx-x86.h b/bfd/elfxx-x86.h
index cc8149d..e11e06b 100644
--- a/bfd/elfxx-x86.h
+++ b/bfd/elfxx-x86.h
@@ -18,6 +18,9 @@
    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
    MA 02110-1301, USA.  */
 
+/* Don't generate unused section symbols.  */
+#define TARGET_KEEP_UNUSED_SECTION_SYMBOLS FALSE
+
 #include "sysdep.h"
 #include "bfd.h"
 #include "bfdlink.h"
diff --git a/bfd/hppabsd-core.c b/bfd/hppabsd-core.c
index d2c8a94..c36e467 100644
--- a/bfd/hppabsd-core.c
+++ b/bfd/hppabsd-core.c
@@ -230,6 +230,7 @@ const bfd_target core_hppabsd_vec =
     0,							   /* symbol prefix */
     ' ',						   /* ar_pad_char */
     16,							   /* ar_max_namelen */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 32 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 16 bit data */
diff --git a/bfd/hpux-core.c b/bfd/hpux-core.c
index 42f8424..03d0de3 100644
--- a/bfd/hpux-core.c
+++ b/bfd/hpux-core.c
@@ -392,6 +392,7 @@ const bfd_target core_hpux_vec =
     ' ',			/* ar_pad_char */
     16,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 32 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 16 bit data */
diff --git a/bfd/i386msdos.c b/bfd/i386msdos.c
index 526561e..6254b2a 100644
--- a/bfd/i386msdos.c
+++ b/bfd/i386msdos.c
@@ -279,6 +279,7 @@ const bfd_target i386_msdos_vec =
     ' ',				/* ar_pad_char */
     16,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
     bfd_getl16, bfd_getl_signed_16, bfd_putl16,	/* data */
diff --git a/bfd/ihex.c b/bfd/ihex.c
index 6543102..13dd106 100644
--- a/bfd/ihex.c
+++ b/bfd/ihex.c
@@ -981,6 +981,7 @@ const bfd_target ihex_vec =
   ' ',				/* AR_pad_char.  */
   16,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* Data.  */
diff --git a/bfd/irix-core.c b/bfd/irix-core.c
index d00f491..e4fb622 100644
--- a/bfd/irix-core.c
+++ b/bfd/irix-core.c
@@ -293,6 +293,7 @@ const bfd_target core_irix_vec =
     ' ',						   /* ar_pad_char */
     16,							   /* ar_max_namelen */
     0,							   /* match_priority */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 32 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 16 bit data */
diff --git a/bfd/mach-o-target.c b/bfd/mach-o-target.c
index 993c974..3b45433 100644
--- a/bfd/mach-o-target.c
+++ b/bfd/mach-o-target.c
@@ -136,6 +136,7 @@ const bfd_target TARGET_NAME =
   ' ',				/* ar_pad_char.  */
   16,				/* ar_max_namelen.  */
   TARGET_PRIORITY,	/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
 #if TARGET_BIG_ENDIAN
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
diff --git a/bfd/mmo.c b/bfd/mmo.c
index a31ddef..4ba62d0 100644
--- a/bfd/mmo.c
+++ b/bfd/mmo.c
@@ -3344,6 +3344,7 @@ const bfd_target mmix_mmo_vec =
   ' ',				/* ar_pad_char */
   16,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* data */
diff --git a/bfd/netbsd-core.c b/bfd/netbsd-core.c
index a1f8820..60fa69d 100644
--- a/bfd/netbsd-core.c
+++ b/bfd/netbsd-core.c
@@ -276,6 +276,7 @@ const bfd_target core_netbsd_vec =
     ' ',			/* ar_pad_char.  */
     16,				/* ar_max_namelen.  */
     0,				/* Match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit data.  */
     NO_GET, NO_GETS, NO_PUT,		/* 32 bit data.  */
     NO_GET, NO_GETS, NO_PUT,		/* 16 bit data.  */
diff --git a/bfd/osf-core.c b/bfd/osf-core.c
index f91b2aa..17cc532 100644
--- a/bfd/osf-core.c
+++ b/bfd/osf-core.c
@@ -187,6 +187,7 @@ const bfd_target core_osf_vec =
     ' ',			/* ar_pad_char */
     16,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 32 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 16 bit data */
diff --git a/bfd/pdp11.c b/bfd/pdp11.c
index 914dcaa..8992f4e 100644
--- a/bfd/pdp11.c
+++ b/bfd/pdp11.c
@@ -4689,6 +4689,7 @@ const bfd_target MY (vec) =
   AR_PAD_CHAR,			/* AR_pad_char.  */
   15,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
      bfd_getp32, bfd_getp_signed_32, bfd_putp32,
      bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* Data.  */
diff --git a/bfd/pef.c b/bfd/pef.c
index 85030e5..93bc933 100644
--- a/bfd/pef.c
+++ b/bfd/pef.c
@@ -1015,6 +1015,7 @@ const bfd_target pef_vec =
   ' ',				/* AR_pad_char.  */
   16,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* Data.  */
@@ -1159,6 +1160,7 @@ const bfd_target pef_xlib_vec =
   ' ',				/* AR_pad_char.  */
   16,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* Data.  */
diff --git a/bfd/plugin.c b/bfd/plugin.c
index d733f6a..d1767b0 100644
--- a/bfd/plugin.c
+++ b/bfd/plugin.c
@@ -719,6 +719,7 @@ const bfd_target plugin_vec =
   '/',				/* ar_pad_char.  */
   15,				/* ar_max_namelen.  */
   255,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
 
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
   bfd_getl32, bfd_getl_signed_32, bfd_putl32,
diff --git a/bfd/ppcboot.c b/bfd/ppcboot.c
index e3ade1c..5cdd7ad 100644
--- a/bfd/ppcboot.c
+++ b/bfd/ppcboot.c
@@ -495,6 +495,7 @@ const bfd_target powerpc_boot_vec =
   ' ',				/* ar_pad_char */
   16,				/* ar_max_namelen */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* data */
diff --git a/bfd/ptrace-core.c b/bfd/ptrace-core.c
index 7cf47af..d21a61c 100644
--- a/bfd/ptrace-core.c
+++ b/bfd/ptrace-core.c
@@ -177,6 +177,7 @@ const bfd_target core_ptrace_vec =
     0,							   /* symbol prefix */
     ' ',						   /* ar_pad_char */
     16,							   /* ar_max_namelen */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 32 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 16 bit data */
diff --git a/bfd/sco5-core.c b/bfd/sco5-core.c
index c543c38..167dba9 100644
--- a/bfd/sco5-core.c
+++ b/bfd/sco5-core.c
@@ -358,6 +358,7 @@ const bfd_target core_sco5_vec =
     ' ',			/* ar_pad_char */
     16,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 32 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 16 bit data */
diff --git a/bfd/som.c b/bfd/som.c
index 5897ae6..872e933 100644
--- a/bfd/som.c
+++ b/bfd/som.c
@@ -6859,6 +6859,7 @@ const bfd_target hppa_som_vec =
   '/',				/* AR_pad_char.  */
   14,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* Data.  */
diff --git a/bfd/srec.c b/bfd/srec.c
index e21d7f8..92faf3d 100644
--- a/bfd/srec.c
+++ b/bfd/srec.c
@@ -1295,6 +1295,7 @@ const bfd_target srec_vec =
   ' ',				/* AR_pad_char.  */
   16,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* Data.  */
@@ -1351,6 +1352,7 @@ const bfd_target symbolsrec_vec =
   ' ',				/* AR_pad_char.  */
   16,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* Data.  */
diff --git a/bfd/syms.c b/bfd/syms.c
index 9559ab4..10ea8bd 100644
--- a/bfd/syms.c
+++ b/bfd/syms.c
@@ -307,6 +307,9 @@ CODE_FRAGMENT
 .     with this name and type in use.  BSF_OBJECT must also be set.  *}
 .#define BSF_GNU_UNIQUE          (1 << 23)
 .
+.  {* This section symbol should be included in the symbol table.  *}
+.#define BSF_SECTION_SYM_USED    (1 << 24)
+.
 .  flagword flags;
 .
 .  {* A pointer to the section to which this symbol is
diff --git a/bfd/targets.c b/bfd/targets.c
index 8086f03..076441b 100644
--- a/bfd/targets.c
+++ b/bfd/targets.c
@@ -133,6 +133,11 @@ DESCRIPTION
 .   (bfd_assert (__FILE__,__LINE__), NULL))
 .#endif
 .
+.{* Defined to TRUE if unused section symbol should be kept.  *}
+.#ifndef TARGET_KEEP_UNUSED_SECTION_SYMBOLS
+.#define TARGET_KEEP_UNUSED_SECTION_SYMBOLS TRUE
+.#endif
+.
 	This is the structure which defines the type of BFD this is.  The
 	<<xvec>> member of the struct <<bfd>> itself points here.  Each
 	module that implements access to a different target under BFD,
@@ -215,6 +220,9 @@ DESCRIPTION
 .     possible targets when more than one target matches.  *}
 .  unsigned char match_priority;
 .
+. {* TRUE if unused section symbols should be kept.  *}
+.  bfd_boolean keep_unused_section_symbols;
+.
 .  {* Entries for byte swapping for data. These are different from the
 .     other entry points, since they don't take a BFD as the first argument.
 .     Certain other handlers could do the same.  *}
@@ -655,6 +663,12 @@ to find an alternative output format that is suitable.
 .  return sy->the_bfd->xvec->flavour;
 .}
 .
+.static inline bfd_boolean
+.bfd_keep_unused_section_symbols (const bfd *abfd)
+.{
+.  return abfd->xvec->keep_unused_section_symbols;
+.}
+.
 */
 
 /* All known xvecs (even those that don't compile on all systems).
diff --git a/bfd/tekhex.c b/bfd/tekhex.c
index 99d54db..6599a4f 100644
--- a/bfd/tekhex.c
+++ b/bfd/tekhex.c
@@ -1008,6 +1008,7 @@ const bfd_target tekhex_vec =
   ' ',				/* AR_pad_char.  */
   16,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* Data.  */
diff --git a/bfd/trad-core.c b/bfd/trad-core.c
index 1a4dbe6..14627cb 100644
--- a/bfd/trad-core.c
+++ b/bfd/trad-core.c
@@ -279,6 +279,7 @@ const bfd_target core_trad_vec =
     ' ',			/* ar_pad_char */
     16,				/* ar_max_namelen */
     0,				/* match priority.  */
+    TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 32 bit data */
     NO_GET, NO_GETS, NO_PUT,		/* 16 bit data */
diff --git a/bfd/verilog.c b/bfd/verilog.c
index a54f6b0..94a9cc8 100644
--- a/bfd/verilog.c
+++ b/bfd/verilog.c
@@ -405,6 +405,7 @@ const bfd_target verilog_vec =
   ' ',				/* AR_pad_char.  */
   16,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* Data.  */
diff --git a/bfd/vms-alpha.c b/bfd/vms-alpha.c
index 72d89e5..94001cc 100644
--- a/bfd/vms-alpha.c
+++ b/bfd/vms-alpha.c
@@ -9792,6 +9792,7 @@ const bfd_target alpha_vms_vec =
   ' ',				/* ar_pad_char.  */
   15,				/* ar_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
   bfd_getl32, bfd_getl_signed_32, bfd_putl32,
   bfd_getl16, bfd_getl_signed_16, bfd_putl16,
diff --git a/bfd/vms-lib.c b/bfd/vms-lib.c
index 3752b91..eaac8af 100644
--- a/bfd/vms-lib.c
+++ b/bfd/vms-lib.c
@@ -2403,6 +2403,7 @@ const bfd_target alpha_vms_lib_txt_vec =
   ' ',				/* ar_pad_char.  */
   15,				/* ar_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
   bfd_getl32, bfd_getl_signed_32, bfd_putl32,
   bfd_getl16, bfd_getl_signed_16, bfd_putl16,
diff --git a/bfd/wasm-module.c b/bfd/wasm-module.c
index 1fde4a5..dc13564 100644
--- a/bfd/wasm-module.c
+++ b/bfd/wasm-module.c
@@ -794,6 +794,7 @@ const bfd_target wasm_vec =
   ' ',				/* AR_pad_char.  */
   255,				/* AR_max_namelen.  */
   0,				/* Match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   /* Routines to byte-swap various sized integers from the data sections.  */
   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
   bfd_getl32, bfd_getl_signed_32, bfd_putl32,
diff --git a/bfd/xsym.c b/bfd/xsym.c
index ea26603..e9283f6 100644
--- a/bfd/xsym.c
+++ b/bfd/xsym.c
@@ -2298,6 +2298,7 @@ const bfd_target sym_vec =
   ' ',				/* AR_pad_char.  */
   16,				/* AR_max_namelen.  */
   0,				/* match priority.  */
+  TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols.  */
   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* Data.  */