PATCH: elf32-i386.c

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

On Thu, Apr 05, 2001 at 03:55:19PM -0700, David Mosberger wrote:
> >>>>> On Tue, 3 Apr 2001 07:42:35 -0700, "H . J . Lu" <hjl@lucon.org> said:
> 
>   HJ> David, I want to avoid changing ELF bfd if all possible.
> 
> Me too.
> 
>   HJ> Could you please try
> 
>   HJ> 	.section .reloc, "a",@progbits
> 
>   HJ> instead of
> 
>   HJ> 	.section .reloc, "a"
> 
> The problem is that BFD completely ignored the incoming section type.
> It's the stupid name-based matching that's causing the problem.  If
> you can come up with a better fix, that would be great.  I did talk to
> Richard Henderson a few months ago and he couldn't come up with a
> better idea either.
> 

Ok. I checked this into CVS.

Thanks.

H.J.
----
2001-03-29  David Mosberger  <davidm@hpl.hp.com>

	* elf32-i386.c (elf_i386_fake_sections): Treat ".reloc" as an
	ordinary "progbits" section.

--- elf32-i386.c.~1.23.~	Thu Mar  8 13:03:59 2001
+++ elf32-i386.c	Thu Mar 29 19:47:33 2001
@@ -2066,6 +2066,44 @@
   return true;
 }
 
+/* Set the correct type for an x86 ELF section.  We do this by the
+   section name, which is a hack, but ought to work.  */
+
+static boolean
+elf_i386_fake_sections (abfd, hdr, sec)
+     bfd *abfd ATTRIBUTE_UNUSED;
+     Elf32_Internal_Shdr *hdr;
+     asection *sec;
+{
+  register const char *name;
+
+  name = bfd_get_section_name (abfd, sec);
+
+  if (strcmp (name, ".reloc") == 0)
+    /*
+     * This is an ugly, but unfortunately necessary hack that is
+     * needed when producing EFI binaries on x86. It tells
+     * elf.c:elf_fake_sections() not to consider ".reloc" as a section
+     * containing ELF relocation info.  We need this hack in order to
+     * be able to generate ELF binaries that can be translated into
+     * EFI applications (which are essentially COFF objects).  Those
+     * files contain a COFF ".reloc" section inside an ELFNN object,
+     * which would normally cause BFD to segfault because it would
+     * attempt to interpret this section as containing relocation
+     * entries for section "oc".  With this hack enabled, ".reloc"
+     * will be treated as a normal data section, which will avoid the
+     * segfault.  However, you won't be able to create an ELFNN binary
+     * with a section named "oc" that needs relocations, but that's
+     * the kind of ugly side-effects you get when detecting section
+     * types based on their names...  In practice, this limitation is
+     * unlikely to bite.
+     */
+    hdr->sh_type = SHT_PROGBITS;
+
+  return true;
+}
+
+
 #define TARGET_LITTLE_SYM		bfd_elf32_i386_vec
 #define TARGET_LITTLE_NAME		"elf32-i386"
 #define ELF_ARCH			bfd_arch_i386
@@ -2096,5 +2134,6 @@
 #define elf_backend_gc_sweep_hook	      elf_i386_gc_sweep_hook
 #define elf_backend_relocate_section	      elf_i386_relocate_section
 #define elf_backend_size_dynamic_sections     elf_i386_size_dynamic_sections
+#define elf_backend_fake_sections 	      elf_i386_fake_sections
 
 #include "elf32-target.h"