Sign extend VMAs on MIPS ELF64

Sign extend VMAs on MIPS ELF64

[Daniel Jacobowitz]

We're careful to mark o32 and n32 addresses as sign extendable for
MIPS, but not n64.  Normally this doesn't matter as N64 uses 64-bit
addresses anyway.  However gcc with -msym32 will use an address
size of 4 for the .debug_info section.  Without this patch GDB
does not sign extend addresses from a MIPS64 Linux kernel built with
-msym32, so e.g. a breakpoint will be set just above 2G instead of at
the very top of memory.

Is this OK?  No regressions on the GDB testsuite on various ABIs.

-- 
Daniel Jacobowitz
CodeSourcery

2007-08-22  Daniel Jacobowitz  <dan@codesourcery.com>

	* elf64-mips.c (elf_backend_sign_extend_vma): Define.

Index: elf64-mips.c
===================================================================
RCS file: /scratch/gcc/repos/src/src/bfd/elf64-mips.c,v
retrieving revision 1.83
diff -u -p -r1.83 elf64-mips.c
--- elf64-mips.c	10 Jul 2007 04:08:11 -0000	1.83
+++ elf64-mips.c	22 Aug 2007 16:47:28 -0000
@@ -3147,6 +3147,8 @@ const struct elf_size_info mips_elf64_si
 #define elf_backend_may_use_rela_p	1
 #define elf_backend_default_use_rela_p	1
 
+#define elf_backend_sign_extend_vma	TRUE
+
 #define elf_backend_write_section	_bfd_mips_elf_write_section
 
 /* We don't set bfd_elf64_bfd_is_local_label_name because the 32-bit

Re: Sign extend VMAs on MIPS ELF64

[Eric Christopher]

On Aug 22, 2007, at 1:17 PM, Daniel Jacobowitz wrote:

> 2007-08-22  Daniel Jacobowitz  <dan@codesourcery.com>
>
> 	* elf64-mips.c (elf_backend_sign_extend_vma): Define.

OK.

-eric