emacs a.out file, self-generated by emacs's "unexec" function in
"unexsunos4.c", is invalid. In particular, its "_end" symbol has
the wrong value. The dynamic linker was using the value of that
symbol to initialize its sbrk break level.
The workaround is to peek at the executable's a.out header in
memory, and calculate what "_end" should be based on the segment
sizes.
I will work out a fix for emacs and send it to the FSF. This
dynamic linker workaround is still worthwhile, if only to avoid
forcing all emacs users to build a new version.
Note: xemacs gives a bogus warning at startup, for related reasons.
The warning is harmless and can safely be ignored. I will send a
patch to the xemacs maintainers to get rid of it, and meanwhile
add a patch file to our port.
things so that it uses the same malloc as is used by the program
being executed. This has several advantages, the big one being
that you can now debug core dumps from dynamically linked programs
and get useful information out of them. Until now, that didn't
work. The internal malloc package placed the tables describing
the loaded shared libraries in a mapped region of high memory that
was not written to core files. Thus the debugger had no way of
determining what was loaded where in memory. Now that the dynamic
linker uses the application's malloc package (normally, but not
necessarily, the system malloc), its tables end up in the regular
heap area where they will be included in core dumps. The debugger
now works very well indeed, thank you very much.
Also ...
Bring the program a little closer to conformance with style(9).
There is still a long way to go.
Add minimal const correctness changes to get rid of compiler warnings
caused by the recent const changes in <dlfcn.h> and <link.h>.
Improve performance by eliminating redundant calculations of symbols'
hash values.
Implemented reading of %fs and %gs from core files.
Print weird floating point values better. We have to convert long
doubles to doubles here because of limitations and bugs in printf()
and floatformat_to_double() (long doubles aren't really supported
and naive converion to double causes exceptions). Conversion loses
information about weird formats (everything becomes a quiet NaN),
and printf() doesn't know about different types of NaNs anyway.
can get their rights as well. ;-) The default remains, of course, Taylor
config.
Demanded by: some people on -hackers
I think this is safe enough to go into RELENG_2_2 as well, if there's
demand.
plain 0 should be used. This happens to work because we #define
NULL to 0, but is stylistically wrong and can cause problems
for people trying to port bits of code to other environments.
PR: 2752
Submitted by: Arne Henrik Juul <arnej@imf.unit.no>
Bring the style of sods.c into better conformance. Add code to
print the contents of each datum being relocated. Correct the logic
that distinguishes between programs, shared libraries, and object
files. Make the entire program "-Wall" clean.
file based on the previous list of directories stored there which
should overcome a weakness of the '-m' switch which can only add
libs. This is an ideal way of updating the hints list after adding
or removing a shlib since it will remove entries that are gone and
doesn't need to have all the directories spelled out each time.
(eg: rm -f /usr/lib/libtcl75*; ldconfig -R) This only works for
version 2 hints files (which we've been generating for a year or
so) which store the path.
reference to the programming manual. Use this near-copy of the version
of hsuser.texinfo in contrib/libreadline instead of the stale near-copy
in contrib/gdb.
Add a -Bforcedynamic option which generates a dynamic object even
if no shared libraries were given in the link.
Make RRS in text section warnings conditional on "-assert pure-text"
so that I can link non-PIC kernel modules without tons of link
errors. Changes to bsd.lib.mk to follow.
Fix a couple of bugs exposed by the fact that the kernel is not
linked at zero.
Reviewed by: jdp
take the easy way out and implement the beginnings of something similar.
Don't worry, the code here is *dormant* so far, some "help" from cvs is
required. This is going in now so that jdp can see what I'm working on.
This is an extension of the previous existing skeleton $FreeBSD$ code.
because 2 references to _initialize_kcorelow (the other one
from kvm-fbsd.c) resulted. This prevented gdb from working correectly.
delete kcorelow.c from XSRCS in the Makefile.
punning the pcb to an array of ints and using magic indices to
access values in it. This should prevent silent breakage from
changes in the pcb.
Supply 0 for unavailable registers instead of punning the tss to
an array of ints and using magic indices to access garbage values
in it. (The registers are in the pcb; there is nothing interesting
in the tss. This should change someday. At least for dumps, all
the registers should be saved, and common_tss is a good place to
put them.)
Removed ancient wrong (disabled) method for reading eip.
sense to have a weak symbol that is not externally visible. This
fixes many of the "relocation burb" warnings produced when compiling
C++ code with "-fpic". Beyond eliminating warnings, it also makes
some things work that didn't work before.
(ignored :-() errors for `make depend' in /sys/i386/boot/*. It's
natural for there to be no libraries there and inconvenient to check
for this in bsd.prog.mk.
ld-specific flags. LDFLAGS is really for ld-related flags for cc,
not for ld, and some flags, e.g., -Bshareable, mean completely
different things to cc and ld. Having the wrong things in LDFLAGS
also broke the standard ${PROG} target. This was kludged around
by using a special rule that depended on LDFLAGS being bogus.
Fixing `make depend' broke the special rule but fixed the standard
rule (except in the DESTDIR case, which was handled more strictly
here than elsewhere).
dependency on `bar' is very unlikely to be correct.
This is a quick fix for broken dependencies in gdb and many other
places. The dependencies on internal libraries are now missing
instead of wrong when `make depend' is run before the libraries
are created.
directory. config.h is always in the current (= object) directory,
so don't search for it.
config.h is not a source for the library, so don't put it in SRCS and
don't make the library depend on it.
Don't put unused flags in CFLAGS.
Simplify using INTERNALLIB*.
- LDADD was wrong for non-uniform obj trees.
- DPADD was wrong for separate obj tres.
Cleaned up nearby messes, mostly ones invoving paths:
- ../libtxi was useless.
- there were too many redefinitions and too many different names for the
same paths.
- use INTERNALLIB* to simplify libtxi/Makefile.
- LDADD was wrong for non-uniform obj trees.
- DPADD was wrong for separate obj tres.
Cleaned up nearby messes, mostly ones invoving paths:
- -I../libtxi was useless.
- there were too many redefinitions and too many different names for the
same paths.
- use INTERNALLIB* to simplify libtxi/Makefile.
UPAGES layout.. it was entirely too comfortable with reading and writing
the U area before. I've changed it to use PT_GETREGS/PT_PUTREGS
ptrace ops instead of READ_U etc. The code to read the registers from
core dumps is a bandaid at best. It seems to have problems reading
core dumps from dynamic linked executables still, but at least static
dumps work.
I desperately need help from a gdb/bfd expert. :-) HELP!!
of binutils. For all architectures and object file formats,
".p2align n" aligns to the next multiple of 2**n. Thus for FreeBSD,
it does exactly the same thing as the traditional ".align".
The old ".align" directive has different meanings in different
object formats, and even in different variants of a.out. Sometimes
is aligns to a multiple of n, and other times it aligns to a multiple
of 2**n. ".p2align" is preferable for use in assembly language
sources, since it makes them more portable to object formats other
than a.out.
