* elf32-mips.c (mips_elf_calculate_relocation): Do not complain

	when _gp_disp is undefined.  Do not check R_MIPS_LO16 for overflow
	when the relocation is against _gp_disp.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index c274a44..78787ad 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,9 @@
+1999-07-13  Mark Mitchell  <mark@codesourcery.com>
+
+       * elf32-mips.c (mips_elf_calculate_relocation): Do not complain
+       when _gp_disp is undefined.  Do not check R_MIPS_LO16 for overflow
+       when the relocation is against _gp_disp.
+
 1999-07-12  Mark Mitchell  <mark@codesourcery.com>
 
        * dwarf2.c (read_attribute): Support DW_FORM_ref8.

diff --git a/bfd/elf32-mips.c b/bfd/elf32-mips.c
index 9d7a074..03d7f3f 100644 (file)
--- a/bfd/elf32-mips.c
+++ b/bfd/elf32-mips.c
@@ -5770,11 +5770,13 @@ mips_elf_calculate_relocation (abfd,
 
          gp_disp_p = true;
        }
-
-      /* If this symbol is defined, calculate its address.  */
-      if ((h->root.root.type == bfd_link_hash_defined
-          || h->root.root.type == bfd_link_hash_defweak)
-         && h->root.root.u.def.section)
+      /* If this symbol is defined, calculate its address.  Note that
+        _gp_disp is a magic symbol, always implicitly defined by the
+        linker, so it's inappropriate to check to see whether or not
+        its defined.  */
+      else if ((h->root.root.type == bfd_link_hash_defined
+               || h->root.root.type == bfd_link_hash_defweak)
+              && h->root.root.u.def.section)
        {
          sec = h->root.root.u.def.section;
          if (sec->output_section)
@@ -5908,7 +5910,22 @@ mips_elf_calculate_relocation (abfd,
       else
        {
          value = addend + gp - p + 4;
-         overflowed_p = mips_elf_overflow_p (value, 16);
+         /* The MIPS ABI requires checking the R_MIPS_LO16 relocation
+            for overflow.  But, on, say, Irix 5, relocations against
+            _gp_disp are normally generated from the .cpload
+            pseudo-op.  It generates code that normally looks like
+            this:
+
+              lui    $gp,%hi(_gp_disp)
+              addiu  $gp,$gp,%lo(_gp_disp)
+              addu   $gp,$gp,$t9
+
+            Here $t9 holds the address of the function being called,
+            as required by the MIPS ELF ABI.  The R_MIPS_LO16
+            relocation can easily overlfow in this situation, but the
+            R_MIPS_HI16 relocation will handle the overflow.
+            Therefore, we consider this a bug in the MIPS ABI, and do
+            not check for overflow here.  */
        }
       break;