[PATCH] Don't crash if .eh_frame CIE is removed because of no FDEs referencing it and no CIEs preceede it

[Jakub Jelinek]

Hi!

This patch fixes NetBSD x86_64 libc build ld segfault.
If a CIE was removed because of no references to it, there is no need for
cie_offset either.
Ok to commit?

2002-01-03  Jakub Jelinek  <jakub@redhat.com>

	* elf-eh-frame.c (_bfd_elf_write_section_eh_frame): Don't crash if
	CIE at .eh_frame start is removed due to no FDEs referencing it.

--- bfd/elf-eh-frame.c.jj	Mon Dec 31 14:07:53 2001
+++ bfd/elf-eh-frame.c	Thu Jan  3 19:09:44 2002
@@ -919,14 +919,23 @@ _bfd_elf_write_section_eh_frame (abfd, s
 	{
 	  if (sec_info->entry[i].cie)
 	    {
-	      cie_offset = sec_info->entry[i].new_offset;
-	      cie_offset += (sec_info->entry[i].sec->output_section->vma
-			     + sec_info->entry[i].sec->output_offset
-			     - sec->output_section->vma
-			     - sec->output_offset);
+	      /* If CIE is removed due to no remaining FDEs referencing it
+		 and there were no CIEs kept before it, sec_info->entry[i].sec
+		 will be zero.  */
+	      if (sec_info->entry[i].sec == NULL)
+		cie_offset = 0;
+	      else
+		{
+		  cie_offset = sec_info->entry[i].new_offset;
+		  cie_offset += (sec_info->entry[i].sec->output_section->vma
+				 + sec_info->entry[i].sec->output_offset
+				 - sec->output_section->vma
+				 - sec->output_offset);
+		}
 	    }
 	  continue;
 	}
+
       if (sec_info->entry[i].cie)
 	{
 	  /* CIE */

	Jakub