[PATCH/i386newframe] Add asssertion to CFI frame unwinder

[PATCH/i386newframe] Add asssertion to CFI frame unwinder

[Mark Kettenis]

This assertion can unfortunately be triggered.  Don't know how to fix
the bug yet, but this makes clear there is a bug.

Mark

Index: ChangeLog
from  Mark Kettenis  <kettenis@gnu.org>
 
	* dwarf-frame.c (dwarf2_frame_cache): Assert that we have a FDE.

Index: dwarf-frame.c
===================================================================
RCS file: /cvs/src/src/gdb/Attic/dwarf-frame.c,v
retrieving revision 1.1.2.6
diff -u -p -r1.1.2.6 dwarf-frame.c
--- dwarf-frame.c 23 May 2003 20:18:32 -0000 1.1.2.6
+++ dwarf-frame.c 29 May 2003 15:47:12 -0000
@@ -483,6 +483,7 @@ dwarf2_frame_cache (struct frame_info *n
 
   /* Find the correct FDE.  */
   fde = dwarf2_frame_find_fde (&fs->pc);
+  gdb_assert (fde != NULL);
 
   /* Extract any interesting information from the CIE.  */
   fs->data_align = fde->cie->data_alignment_factor;

Re: [PATCH/i386newframe] Add asssertion to CFI frame unwinder

[Elena Zannoni]

Mark Kettenis writes:
 > This assertion can unfortunately be triggered.  Don't know how to fix
 > the bug yet, but this makes clear there is a bug.
 > 
 > Mark
 > 
 > Index: ChangeLog
 > from  Mark Kettenis  <kettenis@gnu.org>
 >  
 > 	* dwarf-frame.c (dwarf2_frame_cache): Assert that we have a FDE.
 > 
 > Index: dwarf-frame.c
 > ===================================================================
 > RCS file: /cvs/src/src/gdb/Attic/dwarf-frame.c,v
 > retrieving revision 1.1.2.6
 > diff -u -p -r1.1.2.6 dwarf-frame.c
 > --- dwarf-frame.c 23 May 2003 20:18:32 -0000 1.1.2.6
 > +++ dwarf-frame.c 29 May 2003 15:47:12 -0000
 > @@ -483,6 +483,7 @@ dwarf2_frame_cache (struct frame_info *n
 >  
 >    /* Find the correct FDE.  */
 >    fde = dwarf2_frame_find_fde (&fs->pc);
 > +  gdb_assert (fde != NULL);
 >  
 >    /* Extract any interesting information from the CIE.  */
 >    fs->data_align = fde->cie->data_alignment_factor;


I am running into this in several cases running the testsuite on x86.
For instance for me callfuncs.exp just doesn't do anything, because
the assertion is triggered at startup.
what exactly is happening? 

thanks
elena

Re: [PATCH/i386newframe] Add asssertion to CFI frame unwinder

[Elena Zannoni]

Elena Zannoni writes:
 > Mark Kettenis writes:
 >  > This assertion can unfortunately be triggered.  Don't know how to fix
 >  > the bug yet, but this makes clear there is a bug.
 >  > 
 >  > Mark
 >  > 
 >  > Index: ChangeLog
 >  > from  Mark Kettenis  <kettenis@gnu.org>
 >  >  
 >  > 	* dwarf-frame.c (dwarf2_frame_cache): Assert that we have a FDE.
 >  > 
 >  > Index: dwarf-frame.c
 >  > ===================================================================
 >  > RCS file: /cvs/src/src/gdb/Attic/dwarf-frame.c,v
 >  > retrieving revision 1.1.2.6
 >  > diff -u -p -r1.1.2.6 dwarf-frame.c
 >  > --- dwarf-frame.c 23 May 2003 20:18:32 -0000 1.1.2.6
 >  > +++ dwarf-frame.c 29 May 2003 15:47:12 -0000
 >  > @@ -483,6 +483,7 @@ dwarf2_frame_cache (struct frame_info *n
 >  >  
 >  >    /* Find the correct FDE.  */
 >  >    fde = dwarf2_frame_find_fde (&fs->pc);
 >  > +  gdb_assert (fde != NULL);
 >  >  
 >  >    /* Extract any interesting information from the CIE.  */
 >  >    fs->data_align = fde->cie->data_alignment_factor;
 > 
 > 
 > I am running into this in several cases running the testsuite on x86.
 > For instance for me callfuncs.exp just doesn't do anything, because
 > the assertion is triggered at startup.
 > what exactly is happening? 
 > 
 > thanks
 > elena

Well, this is a problem with the infimous separate debug info. The
.debug_blah sections are in one objfile (the .debug one), while the
.eh_frame is in another (the stripped executable). However, there is
an empty .eh_frame in the .debug file as well. This one is the one
that screws things up. I'll post a patch separately.

elena