GDB, the GNU Project debugger, allows you to see what is going on `inside' another program while it executes -- or what another program was doing at the moment it crashed.
emulparams/ README aix5ppc.sh aix5rs6.sh aixppc.sh aixrs6.sh alpha.sh arcelf.sh arm_epoc_pe.sh arm_wince_pe.sh armaoutb.sh armaoutl.sh armcoff.sh armelf.sh armelf_fbsd.sh armelf_linux.sh armelf_linux_eabi.sh armelf_nbsd.sh armelf_vxworks.sh armelfb.sh armelfb_linux.sh armelfb_linux_eabi.sh armelfb_nbsd.sh armnbsd.sh armnto.sh armpe.sh armsymbian.sh avr1.sh avr2.sh avr3.sh avr4.sh avr5.sh avr6.sh bfin.sh coff_i860.sh coff_sparc.sh crisaout.sh criself.sh crislinux.sh d10velf.sh d30v_e.sh d30v_o.sh d30velf.sh delta68.sh elf32_dlx.sh elf32_i860.sh elf32_i960.sh elf32_sparc.sh elf32_sparc_vxworks.sh elf32_spu.sh elf32am33lin.sh emultempl/ po/ scripttempl/ testsuite/ ChangeLog ChangeLog-0001 ChangeLog-0203 ChangeLog-2004 ChangeLog-2005 ChangeLog-2006 ChangeLog-9197 ChangeLog-9899 MAINTAINERS Makefile.am Makefile.in NEWS README TODO acinclude.m4 aclocal.m4 config.in configure configure.host configure.in configure.tgt deffile.h deffilep.y dep-in.sed elf-hints-local.h fdl.texi gen-doc.texi genscripts.sh h8-doc.texi ld.h ld.texinfo ldcref.c ldctor.c ldctor.h ldemul.c ldemul.h ldexp.c ldexp.h ldfile.c ldfile.h ldgram.y ldint.texinfo ldlang.c ldlang.h ldlex.h ldlex.l ldmain.c ldmain.h ldmisc.c ldmisc.h ldver.c ldver.h ldwrite.c ldwrite.h lexsup.c mri.c mri.h pe-dll.c pe-dll.h pep-dll.c pep-dll.h stamp-h.in sysdep.h