Do not load .eh_frame section from separete object files

We don't need to read the .eh_frame section from the separate
object files, because this data is already present in the
main executable (it needs to, or the program wouldn't work).

We discovered this investigating a problem with the 'next' command,
which was due to unwind failures, which came from the fact that
the .eh_frame was incorrectly relocated.

gdb/ChangeLog (Tristan Gingold):

    * dwarf2-frame.c (dwarf2_build_frame_info): Do not load .eh_frame
    section in separate object files.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index c9e36ff..3e63d48 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2011-07-04  Joel Brobecker  <brobecker@adacore.com>
+
+       * dwarf2-frame.c (dwarf2_build_frame_info): Do not load .eh_frame
+       section in separate object files.
+
 2011-07-04  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
        Fix false GCC warning.

diff --git a/gdb/dwarf2-frame.c b/gdb/dwarf2-frame.c
index 5df3488..b68a773 100644 (file)
--- a/gdb/dwarf2-frame.c
+++ b/gdb/dwarf2-frame.c
@@ -2227,39 +2227,44 @@ dwarf2_build_frame_info (struct objfile *objfile)
   unit->dbase = 0;
   unit->tbase = 0;
 
-  dwarf2_get_section_info (objfile, DWARF2_EH_FRAME,
-                           &unit->dwarf_frame_section,
-                           &unit->dwarf_frame_buffer,
-                           &unit->dwarf_frame_size);
-  if (unit->dwarf_frame_size)
+  if (objfile->separate_debug_objfile_backlink == NULL)
     {
-      asection *got, *txt;
-
-      /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base
-        that is used for the i386/amd64 target, which currently is
-        the only target in GCC that supports/uses the
-        DW_EH_PE_datarel encoding.  */
-      got = bfd_get_section_by_name (unit->abfd, ".got");
-      if (got)
-       unit->dbase = got->vma;
-
-      /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64
-         so far.  */
-      txt = bfd_get_section_by_name (unit->abfd, ".text");
-      if (txt)
-       unit->tbase = txt->vma;
-
-      frame_ptr = unit->dwarf_frame_buffer;
-      while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size)
-       frame_ptr = decode_frame_entry (unit, frame_ptr, 1,
-                                        &cie_table, &fde_table);
-
-      if (cie_table.num_entries != 0)
+      /* Do not read .eh_frame from separate file as they must be also
+         present in the main file.  */
+      dwarf2_get_section_info (objfile, DWARF2_EH_FRAME,
+                               &unit->dwarf_frame_section,
+                               &unit->dwarf_frame_buffer,
+                               &unit->dwarf_frame_size);
+      if (unit->dwarf_frame_size)
         {
-          /* Reinit cie_table: debug_frame has different CIEs.  */
-          xfree (cie_table.entries);
-          cie_table.num_entries = 0;
-          cie_table.entries = NULL;
+          asection *got, *txt;
+
+          /* FIXME: kettenis/20030602: This is the DW_EH_PE_datarel base
+             that is used for the i386/amd64 target, which currently is
+             the only target in GCC that supports/uses the
+             DW_EH_PE_datarel encoding.  */
+          got = bfd_get_section_by_name (unit->abfd, ".got");
+          if (got)
+            unit->dbase = got->vma;
+
+          /* GCC emits the DW_EH_PE_textrel encoding type on sh and ia64
+             so far.  */
+          txt = bfd_get_section_by_name (unit->abfd, ".text");
+          if (txt)
+            unit->tbase = txt->vma;
+
+          frame_ptr = unit->dwarf_frame_buffer;
+          while (frame_ptr < unit->dwarf_frame_buffer + unit->dwarf_frame_size)
+            frame_ptr = decode_frame_entry (unit, frame_ptr, 1,
+                                            &cie_table, &fde_table);
+
+          if (cie_table.num_entries != 0)
+            {
+              /* Reinit cie_table: debug_frame has different CIEs.  */
+              xfree (cie_table.entries);
+              cie_table.num_entries = 0;
+              cie_table.entries = NULL;
+            }
         }
     }