RFA: correctly detect overlapping overlays

[Jim Blandy <jimb@zwingli.cygnus.com>]

Same here.

2001-08-12  Jim Blandy  <jimb@redhat.com>

	* symfile.c (sections_overlap): New function.
	(map_overlay_command): Call sections_overlap, instead of using
	incorrect logic to recognize overlapping sections.

Index: gdb/symfile.c
===================================================================
RCS file: /cvs/cvsfiles/devo/gdb/symfile.c,v
retrieving revision 1.237
diff -c -r1.237 symfile.c
*** gdb/symfile.c	2001/06/14 21:03:18	1.237
--- gdb/symfile.c	2001/08/12 17:28:35
***************
*** 2486,2491 ****
--- 2486,2492 ----
     section_is_overlay(sect):      true if section's VMA != LMA
     pc_in_mapped_range(pc,sec):    true if pc belongs to section's VMA
     pc_in_unmapped_range(...):     true if pc belongs to section's LMA
+    sections_overlap(sec1, sec2):  true if mapped sec1 and sec2 ranges overlap
     overlay_mapped_address(...):   map an address from section's LMA to VMA
     overlay_unmapped_address(...): map an address from section's VMA to LMA
     symbol_overlayed_address(...): Return a "current" address for symbol:
***************
*** 2625,2630 ****
--- 2626,2645 ----
    return 0;
  }
  
+ 
+ /* Return true if the mapped ranges of sections A and B overlap, false
+    otherwise.  */
+ int
+ sections_overlap (asection *a, asection *b)
+ {
+   CORE_ADDR a_start = a->vma;
+   CORE_ADDR a_end   = a->vma + bfd_get_section_size_before_reloc (a);
+   CORE_ADDR b_start = b->vma;
+   CORE_ADDR b_end   = b->vma + bfd_get_section_size_before_reloc (b);
+ 
+   return (a_start < b_end && b_start < a_end);
+ }
+ 
  /* Function: overlay_unmapped_address (PC, SECTION)
     Returns the address corresponding to PC in the unmapped (load) range.
     May be the same as PC.  */
***************
*** 2803,2813 ****
        /* Next, make a pass and unmap any sections that are
           overlapped by this new section: */
        ALL_OBJSECTIONS (objfile2, sec2)
! 	if (sec2->ovly_mapped &&
! 	    sec != sec2 &&
! 	    sec->the_bfd_section != sec2->the_bfd_section &&
! 	    (pc_in_mapped_range (sec2->addr, sec->the_bfd_section) ||
! 	     pc_in_mapped_range (sec2->endaddr, sec->the_bfd_section)))
  	{
  	  if (info_verbose)
  	    printf_filtered ("Note: section %s unmapped by overlap\n",
--- 2818,2828 ----
        /* Next, make a pass and unmap any sections that are
           overlapped by this new section: */
        ALL_OBJSECTIONS (objfile2, sec2)
! 	if (sec2->ovly_mapped
!             && sec != sec2
!             && sec->the_bfd_section != sec2->the_bfd_section
!             && sections_overlap (sec->the_bfd_section,
!                                  sec2->the_bfd_section))
  	{
  	  if (info_verbose)
  	    printf_filtered ("Note: section %s unmapped by overlap\n",