[binutils-gdb] MIPS/opcodes: Only call `bfd_mips_elf_get_abiflags' if BFD64

[Maciej W.Rozycki <macro at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=4df995c77118d07c12fb260dbba0ca2b281324f1

commit 4df995c77118d07c12fb260dbba0ca2b281324f1
Author: Maciej W. Rozycki <macro@imgtec.com>
Date:   Mon Dec 19 11:32:05 2016 +0000

    MIPS/opcodes: Only call `bfd_mips_elf_get_abiflags' if BFD64
    
    Complement commit 5e7fc731f80e ("MIPS/opcodes: Also set disassembler's
    ASE flags from ELF structures") and fix an `--enable-targets=all' GDB
    build regression on 32-bit hosts where the MIPS target is a secondary:
    
    ../opcodes/libopcodes.a(mips-dis.o): In function `set_default_mips_dis_options':
    mips-dis.c:(.text+0x906): undefined reference to `bfd_mips_elf_get_abiflags'
    collect2: error: ld returned 1 exit status
    make[2]: *** [gdb] Error 1
    
    by avoiding making a call to the `bfd_mips_elf_get_abiflags' function,
    which is not available, because there is no MIPS/ELF BFD included in
    32-bit BFD builds.  This call is only made from a conditional code block
    guarded by a check against `bfd_target_elf_flavour', which is dead in
    such a configuration, however cannot be optimized away by the compiler.
    Also some other MIPS BFDs may be available, such as a.out, ECOFF or PE,
    so the disassembler has to remain functional.
    
    	opcodes/
    	* mips-dis.c (set_default_mips_dis_options) [BFD64]: Only call
    	`bfd_mips_elf_get_abiflags' here.

Diff:
---
 opcodes/ChangeLog  |  5 +++++
 opcodes/mips-dis.c | 11 +++++++++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog
index d247bac..2618f90 100644
--- a/opcodes/ChangeLog
+++ b/opcodes/ChangeLog
@@ -1,3 +1,8 @@
+2016-12-19  Maciej W. Rozycki  <macro@imgtec.com>
+
+	* mips-dis.c (set_default_mips_dis_options) [BFD64]: Only call
+	`bfd_mips_elf_get_abiflags' here.
+
 2016-12-16  Nick Clifton  <nickc@redhat.com>
 
 	* arm-dis.c (print_insn_thumb32): Fix compile time warning
diff --git a/opcodes/mips-dis.c b/opcodes/mips-dis.c
index c30bbd0..cd9893e 100644
--- a/opcodes/mips-dis.c
+++ b/opcodes/mips-dis.c
@@ -846,8 +846,15 @@ set_default_mips_dis_options (struct disassemble_info *info)
     {
       struct bfd *abfd = info->section->owner;
       Elf_Internal_Ehdr *header = elf_elfheader (abfd);
-      Elf_Internal_ABIFlags_v0 *abiflags = bfd_mips_elf_get_abiflags (abfd);
-
+      Elf_Internal_ABIFlags_v0 *abiflags = NULL;
+
+      /* We won't ever get here if !BFD64, because we won't then have
+	 a MIPS/ELF BFD, however we need to guard against a link error
+	 in a `--enable-targets=...' configuration with a 32-bit host,
+	 where the MIPS target is a secondary.  */
+#ifdef BFD64
+      abiflags = bfd_mips_elf_get_abiflags (abfd);
+#endif
       /* If an ELF "newabi" binary, use the n32/(n)64 GPR names.  */
       if (is_newabi (header))
 	mips_gpr_names = mips_gpr_names_newabi;