MIPS: Preset EF_MIPS_ABI2 with n32 ELF objects

Fix a bug in MIPS n32 ELF object file generation and make such objects
consistent with the n32 BFD requested, by presetting the EF_MIPS_ABI2
flag in the `e_flags' member of the newly created ELF file header, as it
is this flag that tells n32 objects apart from o32 objects.

This flag will then stay set through to output file generation for
writers such as GAS or GDB's `generate-core-file' command.  Readers will
overwrite the whole of `e_flags' along with the rest of the ELF file
header in `elf_swap_ehdr_in' and then verify in `mips_elf_n32_object_p'
that the flag is still set before accepting an input file as an n32
object.

The issue was discovered with GDB's `generate-core-file' command making
o32 core files out of n32 debuggees.

	bfd/
	* elfn32-mips.c (mips_elf_n32_mkobject): New prototype and
	function.
	(bfd_elf32_mkobject): Use `mips_elf_n32_mkobject' rather than
	`_bfd_mips_elf_mkobject'.

	gas/
	* config/tc-mips.c (mips_elf_final_processing): Don't set
	EF_MIPS_ABI2 in `e_flags'.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index f628a61ee3b9dfa30dc259ec4d2543fd1519aa57..fde334deb9ba7f28c9ec9bbf4a20b58d5a2037c6 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,10 @@
+2017-10-23  Maciej W. Rozycki  <macro@imgtec.com>
+
+       * elfn32-mips.c (mips_elf_n32_mkobject): New prototype and
+       function.
+       (bfd_elf32_mkobject): Use `mips_elf_n32_mkobject' rather than
+       `_bfd_mips_elf_mkobject'.
+
 2017-10-22  Hans-Peter Nilsson  <hp@axis.com>
 
        PR gas/22304

diff --git a/bfd/elfn32-mips.c b/bfd/elfn32-mips.c
index fdae18365e6bf3844d9b169a6e20344f27253321..9ac2da3689d5d233f02dcf1d588623fba130cba3 100644 (file)
--- a/bfd/elfn32-mips.c
+++ b/bfd/elfn32-mips.c
@@ -84,6 +84,8 @@ static bfd_boolean elf_n32_mips_grok_freebsd_prstatus
   (bfd *, Elf_Internal_Note *);
 static irix_compat_t elf_n32_mips_irix_compat
   (bfd *);
+static bfd_boolean mips_elf_n32_mkobject
+  (bfd *);
 
 extern const bfd_target mips_elf32_n_be_vec;
 extern const bfd_target mips_elf32_n_le_vec;
@@ -3643,6 +3645,21 @@ elf_n32_mips_irix_compat (bfd *abfd)
     return ict_none;
 }
 \f
+/* Make an n32 MIPS object.  We need to set the n32 ABI flag in
+   `e_flags' to tell the object apart from an o32 object.  */
+
+static bfd_boolean
+mips_elf_n32_mkobject (bfd *abfd)
+{
+  bfd_boolean ret;
+
+  ret = _bfd_mips_elf_mkobject (abfd);
+  if (ret)
+    elf_elfheader (abfd)->e_flags |= EF_MIPS_ABI2;
+
+  return ret;
+}
+\f
 /* ECOFF swapping routines.  These are used when dealing with the
    .mdebug section, which is in the ECOFF debugging format.  */
 static const struct ecoff_debug_swap mips_elf32_ecoff_debug_swap = {
@@ -3775,7 +3792,7 @@ static const struct ecoff_debug_swap mips_elf32_ecoff_debug_swap = {
 #define bfd_elf32_bfd_set_private_flags        _bfd_mips_elf_set_private_flags
 #define bfd_elf32_bfd_print_private_bfd_data \
                                        _bfd_mips_elf_print_private_bfd_data
-#define bfd_elf32_mkobject             _bfd_mips_elf_mkobject
+#define bfd_elf32_mkobject             mips_elf_n32_mkobject
 
 /* Support for SGI-ish mips targets using n32 ABI.  */
 

diff --git a/gas/ChangeLog b/gas/ChangeLog
index af915ff45040d1368a4a88a5cad119540131e58b..44debdc1d7605dbf6ef4ba4d99b60e07686836f6 100644 (file)
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,8 @@
+2017-10-23  Maciej W. Rozycki  <macro@imgtec.com>
+
+       * config/tc-mips.c (mips_elf_final_processing): Don't set
+       EF_MIPS_ABI2 in `e_flags'.
+
 2017-10-22  Hans-Peter Nilsson  <hp@axis.com>
 
        PR gas/22304

diff --git a/gas/config/tc-mips.c b/gas/config/tc-mips.c
index e4351f7a490bb792281240f0edc721f6673d29a5..040a373adbc71cb5c72778333dd49af12295d76d 100644 (file)
--- a/gas/config/tc-mips.c
+++ b/gas/config/tc-mips.c
@@ -19140,10 +19140,8 @@ mips_elf_final_processing (void)
       else
        elf_elfheader (stdoutput)->e_flags |= E_MIPS_ABI_EABI32;
     }
-  else if (mips_abi == N32_ABI)
-    elf_elfheader (stdoutput)->e_flags |= EF_MIPS_ABI2;
 
-  /* Nothing to do for N64_ABI.  */
+  /* Nothing to do for N32_ABI or N64_ABI.  */
 
   if (mips_32bitmode)
     elf_elfheader (stdoutput)->e_flags |= EF_MIPS_32BITMODE;