* elf-bfd.h (elf_backend_data): Add elf_backend_eh_frame_address_size.

	(_bfd_elf_eh_frame_address_size): Declare.
	* elfxx-target.h (elf_backend_eh_frame_address_size): Define a default.
	(elfNN_bed): Initialize elf_backend_eh_frame_address_size.
	* elfxx-mips.h (_bfd_mips_elf_eh_frame_address_size): Declare.
	(elf_backend_eh_frame_address_size): Define.
	* elfxx-mips.c (_bfd_mips_elf_eh_frame_address_size): New function.
	* elf-eh-frame.c (_bfd_elf_discard_section_eh_frame): Get the address
	size from the new backend hook.
	(_bfd_elf_write_section_eh_frame): Likewise.
	(_bfd_elf_eh_frame_address_size): New function.

6 files changed, 112 insertions, 5 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index b0f0666..c76d939 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,17 @@
+2005-01-31  Richard Sandiford  <rsandifo@redhat.com>
+
+	* elf-bfd.h (elf_backend_data): Add elf_backend_eh_frame_address_size.
+	(_bfd_elf_eh_frame_address_size): Declare.
+	* elfxx-target.h (elf_backend_eh_frame_address_size): Define a default.
+	(elfNN_bed): Initialize elf_backend_eh_frame_address_size.
+	* elfxx-mips.h (_bfd_mips_elf_eh_frame_address_size): Declare.
+	(elf_backend_eh_frame_address_size): Define.
+	* elfxx-mips.c (_bfd_mips_elf_eh_frame_address_size): New function.
+	* elf-eh-frame.c (_bfd_elf_discard_section_eh_frame): Get the address
+	size from the new backend hook.
+	(_bfd_elf_write_section_eh_frame): Likewise.
+	(_bfd_elf_eh_frame_address_size): New function.
+
 2005-01-31  Andrew Cagney  <cagney@gnu.org>
 
 	* configure: Regenerate to track ../gettext.m4.
diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h
index 6645c9a..f2a063b 100644
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@@ -906,6 +906,12 @@ struct elf_backend_data
   bfd_boolean (*elf_backend_ignore_discarded_relocs)
     (asection *);
 
+  /* This function returns the width of FDE pointers in bytes, or 0 if
+     that can't be determined for some reason.  The default definition
+     goes by the bfd's EI_CLASS.  */
+  unsigned int (*elf_backend_eh_frame_address_size)
+    (bfd *, asection *);
+
   /* These functions tell elf-eh-frame whether to attempt to turn
      absolute or lsda encodings into pc-relative ones.  The default
      definition enables these transformations.  */
@@ -1381,6 +1387,8 @@ extern void _bfd_elf_sprintf_vma
 extern void _bfd_elf_fprintf_vma
   (bfd *, void *, bfd_vma);
 
+extern unsigned int _bfd_elf_eh_frame_address_size
+  (bfd *, asection *);
 extern bfd_byte _bfd_elf_encode_eh_address
   (bfd *abfd, struct bfd_link_info *info, asection *osec, bfd_vma offset,
    asection *loc_sec, bfd_vma loc_offset, bfd_vma *encoded);
diff --git a/bfd/elf-eh-frame.c b/bfd/elf-eh-frame.c
index ab316ad..389f6f3 100644
--- a/bfd/elf-eh-frame.c
+++ b/bfd/elf-eh-frame.c
@@ -418,8 +418,10 @@ _bfd_elf_discard_section_eh_frame
      it (it would need to use 64-bit .eh_frame format anyway).  */
   REQUIRE (sec->size == (unsigned int) sec->size);
 
-  ptr_size = (elf_elfheader (abfd)->e_ident[EI_CLASS]
-	      == ELFCLASS64) ? 8 : 4;
+  ptr_size = (get_elf_backend_data (abfd)
+	      ->elf_backend_eh_frame_address_size (abfd, sec));
+  REQUIRE (ptr_size != 0);
+
   buf = ehbuf;
   last_cie = NULL;
   last_cie_inf = NULL;
@@ -987,12 +989,14 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
   unsigned int ptr_size;
   struct eh_cie_fde *ent;
 
-  ptr_size = (elf_elfheader (sec->owner)->e_ident[EI_CLASS]
-	      == ELFCLASS64) ? 8 : 4;
-
   if (sec->sec_info_type != ELF_INFO_TYPE_EH_FRAME)
     return bfd_set_section_contents (abfd, sec->output_section, contents,
 				     sec->output_offset, sec->size);
+
+  ptr_size = (get_elf_backend_data (abfd)
+	      ->elf_backend_eh_frame_address_size (abfd, sec));
+  BFD_ASSERT (ptr_size != 0);
+
   sec_info = elf_section_data (sec)->sec_info;
   htab = elf_hash_table (info);
   hdr_info = &htab->eh_info;
@@ -1407,6 +1411,14 @@ _bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
   return retval;
 }
 
+/* Return the width of FDE addresses.  This is the default implementation.  */
+
+unsigned int
+_bfd_elf_eh_frame_address_size (bfd *abfd, asection *sec ATTRIBUTE_UNUSED)
+{
+  return elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64 ? 8 : 4;
+}
+
 /* Decide whether we can use a PC-relative encoding within the given
    EH frame section.  This is the default implementation.  */
 
diff --git a/bfd/elfxx-mips.c b/bfd/elfxx-mips.c
index 9ec9c86..595c9df 100644
--- a/bfd/elfxx-mips.c
+++ b/bfd/elfxx-mips.c
@@ -4248,6 +4248,72 @@ _bfd_mips_elf_symbol_processing (bfd *abfd, asymbol *asym)
     }
 }
 
+/* Implement elf_backend_eh_frame_address_size.  This differs from
+   the default in the way it handles EABI64.
+
+   EABI64 was originally specified as an LP64 ABI, and that is what
+   -mabi=eabi normally gives on a 64-bit target.  However, gcc has
+   historically accepted the combination of -mabi=eabi and -mlong32,
+   and this ILP32 variation has become semi-official over time.
+   Both forms use elf32 and have pointer-sized FDE addresses.
+
+   If an EABI object was generated by GCC 4.0 or above, it will have
+   an empty .gcc_compiled_longXX section, where XX is the size of longs
+   in bits.  Unfortunately, ILP32 objects generated by earlier compilers
+   have no special marking to distinguish them from LP64 objects.
+
+   We don't want users of the official LP64 ABI to be punished for the
+   existence of the ILP32 variant, but at the same time, we don't want
+   to mistakenly interpret pre-4.0 ILP32 objects as being LP64 objects.
+   We therefore take the following approach:
+
+      - If ABFD contains a .gcc_compiled_longXX section, use it to
+        determine the pointer size.
+
+      - Otherwise check the type of the first relocation.  Assume that
+        the LP64 ABI is being used if the relocation is of type R_MIPS_64.
+
+      - Otherwise punt.
+
+   The second check is enough to detect LP64 objects generated by pre-4.0
+   compilers because, in the kind of output generated by those compilers,
+   the first relocation will be associated with either a CIE personality
+   routine or an FDE start address.  Furthermore, the compilers never
+   used a special (non-pointer) encoding for this ABI.
+
+   Checking the relocation type should also be safe because there is no
+   reason to use R_MIPS_64 in an ILP32 object.  Pre-4.0 compilers never
+   did so.  */
+
+unsigned int
+_bfd_mips_elf_eh_frame_address_size (bfd *abfd, asection *sec)
+{
+  if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64)
+    return 8;
+  if ((elf_elfheader (abfd)->e_flags & EF_MIPS_ABI) == E_MIPS_ABI_EABI64)
+    {
+      bfd_boolean long32_p, long64_p;
+
+      long32_p = bfd_get_section_by_name (abfd, ".gcc_compiled_long32") != 0;
+      long64_p = bfd_get_section_by_name (abfd, ".gcc_compiled_long64") != 0;
+      if (long32_p && long64_p)
+	return 0;
+      if (long32_p)
+	return 4;
+      if (long64_p)
+	return 8;
+
+      if (sec->reloc_count > 0
+	  && elf_section_data (sec)->relocs != NULL
+	  && (ELF32_R_TYPE (elf_section_data (sec)->relocs[0].r_info)
+	      == R_MIPS_64))
+	return 8;
+
+      return 0;
+    }
+  return 4;
+}
+
 /* There appears to be a bug in the MIPSpro linker that causes GOT_DISP
    relocations against two unnamed section symbols to resolve to the
    same address.  For example, if we have code like:
diff --git a/bfd/elfxx-mips.h b/bfd/elfxx-mips.h
index 0a684d9..de48c63 100644
--- a/bfd/elfxx-mips.h
+++ b/bfd/elfxx-mips.h
@@ -24,6 +24,8 @@ extern bfd_boolean _bfd_mips_elf_new_section_hook
   (bfd *, asection *);
 extern void _bfd_mips_elf_symbol_processing
   (bfd *, asymbol *);
+extern unsigned int _bfd_mips_elf_eh_frame_address_size
+  (bfd *, asection *);
 extern bfd_boolean _bfd_mips_elf_name_local_section_symbols
   (bfd *);
 extern bfd_boolean _bfd_mips_elf_section_processing
@@ -124,3 +126,4 @@ extern struct bfd_elf_special_section const _bfd_mips_elf_special_sections[];
 #define elf_backend_name_local_section_symbols \
   _bfd_mips_elf_name_local_section_symbols
 #define elf_backend_special_sections _bfd_mips_elf_special_sections
+#define elf_backend_eh_frame_address_size _bfd_mips_elf_eh_frame_address_size
diff --git a/bfd/elfxx-target.h b/bfd/elfxx-target.h
index a9d49c3..baad96d 100644
--- a/bfd/elfxx-target.h
+++ b/bfd/elfxx-target.h
@@ -442,6 +442,9 @@
 #ifndef elf_backend_ignore_discarded_relocs
 #define elf_backend_ignore_discarded_relocs	NULL
 #endif
+#ifndef elf_backend_eh_frame_address_size
+#define elf_backend_eh_frame_address_size _bfd_elf_eh_frame_address_size
+#endif
 #ifndef elf_backend_can_make_relative_eh_frame
 #define elf_backend_can_make_relative_eh_frame	_bfd_elf_can_make_relative
 #endif
@@ -573,6 +576,7 @@ static const struct elf_backend_data elfNN_bed =
   elf_backend_reloc_type_class,
   elf_backend_discard_info,
   elf_backend_ignore_discarded_relocs,
+  elf_backend_eh_frame_address_size,
   elf_backend_can_make_relative_eh_frame,
   elf_backend_can_make_lsda_relative_eh_frame,
   elf_backend_encode_eh_address,