* Re: Proposal: convert function definitions to prototyped form
[not found] ` <3937816C.E66B9AE0@cygnus.com>
@ 2000-06-03 0:13 ` Kevin Buettner
0 siblings, 0 replies; 5+ messages in thread
From: Kevin Buettner @ 2000-06-03 0:13 UTC (permalink / raw)
To: Andrew Cagney; +Cc: gdb
On Jun 2, 7:42pm, Andrew Cagney wrote:
> The only concern I have is, given the slightly more complex nature of
> the script (compared to PARAMS) there is a possibility that the
> conversion re-orders or re-types the argument list. With that in mind,
> should a pre-cursor to this be to least have prototypes for all
> (global?) functions (-Wmissing-prototypes?) or only do the conversion
> when there is a prototype visible?
I've given this matter a lot of thought.
I agree that it would be desirable to have prototypes for all
functions. Unfortunately, while it is easy to generate prototypes,
it's not so easy to know where to stick them. Also, even if we had
prototypes in place, there's no guarantee that we'd catch the errors
after a few builds because I think there's some code in gdb (though I
don't know how much) that never gets built! (Due to ifdefs and
near obsolete ports.)
What we really need is a method for vetting all of the changes
immediately after running the script. I.e, we need to make sure that
the conversion does no reordering or retyping of any argument list.
Also, we need to make sure that the rewritten function declaration
is syntactically correct.
While examining the diffs (made with the -u switch) an idea occurred
to me. Consider the following example:
diff -ur ../../orig/gdb-sourceware/wrapper.c ./wrapper.c
--- ../../orig/gdb-sourceware/wrapper.c Sat May 27 17:10:27 2000
+++ ./wrapper.c Thu Jun 1 23:33:16 2000
@@ -57,11 +57,8 @@
static int wrap_parse_and_eval_type (char *);
int
-gdb_parse_exp_1 (stringptr, block, comma, expression)
- char **stringptr;
- struct block *block;
- int comma;
- struct expression **expression;
+gdb_parse_exp_1 (char **stringptr, struct block *block, int comma,
+ struct expression **expression)
{
struct gdb_wrapper_arguments args;
args.args[0].pointer = stringptr;
In the above diff, the lines prepended with `-' represent the original
K&R definition. And the lines prepended with `+' represent the
transformed code. Moreover, the diff is extremely regular in this
respect. So...
If you take the lines which begin with `+', prepend the type on the
line before the `-' lines and tack a semicolon onto the end, you end
up with a prototype declaration. And, if you take the lines beginning
with `-', again tack the type onto the front and put a function body
underneath it, you have a K&R style (traditional) function definition.
Now if you put these into a file with the prototype first and the K&R
definition later on, you can run "gcc -Wall" on it to see if any
warnings are produced. Obviously, if we get warnings, we need to look
closer to see if something went wrong with the fix-decls conversion.
Of course, there are other details to consider, like making sure that
all of the types, structs, unions, and enums are declared. Also,
in a source tree as big as gdb, we'll likely wind up with a number
of functions with the same name, so some method of disambiguating
these will be necessary. And then of course, there's the matter
of no declared return type and other oddments.
I've written a script called ``check-decls'' which performs these
transformations on the diff output. When I run it on the above diff,
it produces the following output (indented by four spaces by me for
readability)
struct block { int f0; };
struct expression { int f1; };
#define INLINE
#define private
#define CONST const
#define NORETURN
void init___ (void *);
int gdb_parse_exp_1 (char **stringptr, struct block *block, int comma,
struct expression **expression);
int
gdb_parse_exp_1 (stringptr, block, comma, expression)
char **stringptr;
struct block *block;
int comma;
struct expression **expression;
{
int ret;
init___ (&ret);
return ret;
}
void
use___ (void)
{
}
The use___ () function isn't interesting in this example, but it would
be if there had been a static declaration.
Here's what happens when I run it on *all* of the diffs:
ocotillo:ptests$ ./check-decls <declsdiff >prog.c
ocotillo:ptests$ wc prog.c
50235 112228 960827 prog.c
ocotillo:ptests$ gcc -c -Wall prog.c
prog.c: In function `exit':
prog.c:39303: warning: function declared `noreturn' has a `return' statement
prog.c: At top level:
prog.c:45903: parse error before `arg_type'
prog.c: In function `value_primitive_field':
prog.c:45907: declaration for parameter `arg_type' but no such parameter
prog.c:45906: declaration for parameter `fieldno' but no such parameter
prog.c:45905: declaration for parameter `offset' but no such parameter
prog.c:45904: declaration for parameter `arg1' but no such parameter
prog.c:45908: argument `arg_type' doesn't match prototype
prog.c:5886: prototype declaration
prog.c:45908: argument `arg1' doesn't match prototype
prog.c:5886: prototype declaration
The `exit' warning is due to the fact that there's a declaration and
definition of exit() from standalone.c. It is of no concern.
The error following this warning looks more serious. Here's the declaration
and the definition of the function involved:
value_ptr value_primitive_field (register value_ptr arg1, int offset,
register int fieldno, register struct type *arg_type);
value_ptr
value_primitive_field (arg1, offset, fieldno, arg_type)
register value_ptr arg1;
int offset;
register int fieldno;
register struct type *arg_type;
{
value_ptr ret;
init___ (&ret);
return ret;
}
I looked at this for a long, long time and didn't see anything wrong.
Finally, I realized that arg_type was a type from a different file.
(Which is one of the problems with throwing everything into one big
pot.) Anyway, here's the type that the script declared:
typedef struct t44 { int f44; } arg_type;
And here's the (transformed) definition which caused it to be defined:
bool_t
xdr_arg_type(xdrs, objp)
XDR *xdrs;
arg_type *objp;
{
bool_t ret;
init___ (&ret);
return ret;
}
So it turns out that it's nothing to worry about.
And that's it. There are no other warnings or errors. Which means
that the transformation was successful and didn't mess up any of
the parameter types.
The check-decls script is below. One might argue that it is about as
complex as the fix-decls script. This is true, but the code which
actually extracts the `-' and `+' lines is fairly simple. Also, after
being extracted, there are no transformations made to these lines
aside from appending ___<num> to the function name if the script
detects that the function name has already been seen. Most
importantly, the parameter lists are not rewritten in any way.
Most of the complexity is in the analysis and generation of the
type, struct, enum, and union declarations. But uniqueness of
these is easy to verify. Plus, if something is screwed up, the
compiler complains.
--- check-decls ---
#!/usr/bin/perl -w
# Feed this script a unidiff after running fix-decls and it generates
# (on stdout) a program which may be used to test the validity of the
# conversion. Just run the result through gcc -Wall and if it
# generates any warnings, there's a problem...
undef $/; # slurp mode
my $diff = <>; # read entire diff in $diff;
my $decls = '';
my $defns = '';
my %userstructs = ();
my %userenums = ();
my %usertypes = ();
my %funcnames = ();
my $funcname_gensym = 0; # for names that clash
my @needuse;
while ($diff =~
/ (
^ # beginning of line
[^\n]+ # everything til the end of line
)
\n # newline
(
(?:
^ # beginning of line
- # minus sign
(?: \n # either just a newline
| # -- or --
[^-\n] # any character but minus and newline
[^\n]* # the rest of the line
\n # including the newline
)
)+ # one or more of the above
)
(
(?:
^ # beginning of line
\+ # plus sign
[^+] # any character but plus
[^\n]* # the rest of the line
\n # including the newline
)+ # one or more of the above
)
/mgx) {
my ($rettype, $traddecl, $isodecl) = ($1, $2, $3);
# Remove leading diff character from the lines extracted
foreach ($rettype, $traddecl, $isodecl) {
s/^.//mg;
}
# Find type names in parameter list
my $parmdecls = $traddecl;
$parmdecls =~ s/^\w+\s*\([^)]*\)//;
foreach my $parm (split /\s*;\s*/, $parmdecls) {
$parm =~ s/\s*\**\w+(,|$).*$//;
analyze_type($parm);
}
# Resolve collisions between function name (either due to statics
# or due to the names being in different branches of an ifdef)
my ($funcname) = $traddecl =~ /^(\w+)/;
if (defined $funcnames{$funcname}) {
foreach ($traddecl, $isodecl) {
s/\b$funcname\b/${funcname}___$funcname_gensym/;
}
$funcname .= "___$funcname_gensym";
$funcname_gensym++;
}
$funcnames{$funcname} = $funcname;
# Nuke comments in the return type
$rettype =~ s#/\*.*?\*/##g;
# Nuke partial comment in return type
$rettype =~ s#^.*?\*/##;
# Eliminate ``CALLBACK'' from return type
$rettype =~ s/\bCALLBACK\b//;
# Eliminate ``extern'' from return type
$rettype =~ s/\bextern\b//;
# Eliminate leading and trailing spaces from return type
$rettype =~ s/^\s*//;
$rettype =~ s/\s*$//;
if (($rettype =~ /^#/) || ($rettype eq '')) {
# preprocessor line or empty string
$rettype = 'int';
} elsif ($rettype eq "static") {
$rettype = 'static int';
} elsif ($rettype eq "private") {
$rettype = 'static int';
} else {
analyze_type($rettype);
}
$isodecl =~ s/\n\Z/;\n/;
$decls .= "$rettype $isodecl";
if ($rettype =~ /\bvoid$/) {
$defns .= "$rettype\n$traddecl\{\n}\n\n";
} else {
$defns .= "$rettype\n$traddecl\{\n $rettype ret;\n"
. " init___ (&ret);\n return ret;\n}\n\n";
}
if ($rettype =~/\bstatic\b/) {
push @needuse, $funcname;
}
}
my $typeidx = 0;
foreach $key (sort keys %usertypes) {
print "typedef struct t$typeidx { int f$typeidx; } $key;\n";
$typeidx++;
}
foreach $key (sort keys %userstructs) {
print "$key { int f$typeidx; };\n";
$typeidx++;
}
foreach $key (sort keys %userenums) {
print "$key { e$typeidx };\n";
$typeidx++;
}
print "#define INLINE\n";
print "#define private\n";
print "#define CONST const\n";
print "#define NORETURN\n";
print "void init___ (void *);\n";
print $decls;
print "\n";
print $defns;
print "void\nuse___ (void)\n{\n";
foreach (@needuse) {
print " init___ ($_);\n";
}
print "}\n";
sub analyze_type {
my ($parm) = @_;
$parm =~ s/\s*\**\s*$//;
my $type;
if ($parm =~ /\b(struct|union)\b/) {
$parm =~ s/\A.*\b(struct|union)\b/$1/s;
$parm =~ s/\s*\**\s*\Z//s;
$userstructs{$parm} = $parm;
} elsif ($parm =~ /\b(enum)\b/) {
$parm =~ s/\A.*\b(enum)\b/$1/s;
$parm =~ s/\s*\**\s*\Z//s;
$userenums{$parm} = $parm;
} elsif ((($type) = $parm =~ /(\w+)$/)
&& ($type !~ /^(int|char|long|short|unsigned|double
|register|void|const|static)$/x)) {
$usertypes{$type} = $type;
}
}
--- end check-decls ---
From kevinb@cygnus.com Sat Jun 03 00:21:00 2000
From: Kevin Buettner <kevinb@cygnus.com>
To: Andrew Cagney <ac131313@cygnus.com>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Sat, 03 Jun 2000 00:21:00 -0000
Message-id: <1000603072049.ZM32430@ocotillo.lan>
References: <1000602075018.ZM29997@ocotillo.lan> <3937816C.E66B9AE0@cygnus.com> <ac131313@cygnus.com>
X-SW-Source: 2000-06/msg00029.html
Content-length: 198
On Jun 2, 7:42pm, Andrew Cagney wrote:
> PS: You may want to add gdb/*-share to the list of directories to avoid.
I can certainly do this, but I'd like to know why they shouldn't be
converted...
From eliz@delorie.com Sat Jun 03 03:58:00 2000
From: Eli Zaretskii <eliz@delorie.com>
To: kevinb@cygnus.com
Cc: taylor@cygnus.com, gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Sat, 03 Jun 2000 03:58:00 -0000
Message-id: <200006031058.GAA12885@indy.delorie.com>
References: <200006021539.LAA25912@texas.cygnus.com> <1000602191042.ZM30936@ocotillo.lan>
X-SW-Source: 2000-06/msg00030.html
Content-length: 2307
> Date: Fri, 2 Jun 2000 12:10:42 -0700
> From: Kevin Buettner <kevinb@cygnus.com>
>
> > I've used protoize before with good results. It was a fairly
> > substantial project, though not as big as gdb.
>
> Okay. Out of curiousity, did the project in question have a large
> number of active developers?
I think the real problem is not the number of developers, but the
number of different configurations, and also different data types and
functions concealed behind macros. `protoize' needs everything to be
explicit, so it is not easy to run it on multi-platform project that
uses macros to hide system dependencies (since you want the same
macros back in the reformatted sources).
This is a disadvantage of `protoize'. Its significant advantage is
that its output is *always* correct, because it takes the info ``from
the horse's mouth'': the compiler itself. In contrast, a script is
simply a text-processing tool: it really doesn't understand the
semantics of the source. In fact, it doesn't really understand the
syntax very well.
So with a script, we will always need a verification tool that can be
trusted to find any potential bugs introduced by reformatting.
> > I'd be tempted to do a build before running your script; stash away the
> > object files; run the script; do another build; compare the object
> > files...
>
> Good idea. I'll have to see what gcc does to compare object files.
> (I don't think a simple cmp works for ELF files.)
Comparing object files generally doesn't work. COFF (at least the
variety used by DJGPP) is another case: if I compile the same source
twice in a row, I get different object files (IIRC, the time stamp is
recorded inside).
One method I can suggest is to compile the source without
optimizations, then run "objdump --disassemble" and compare the output
of `objdump' for the two source files (original and reformatted). (I
suggest to disable optimizations because it's possible that ANSI
source allows the compiler to produce more optimal code that the K&R
source.)
Note that, since you need to compile the source to make sure
reformatting didn't screw up anything, you essentially get the same
problems you had with `protoize', albeit through the back door: you
need to build for all supported configurations to make sure nothing's
broken.
From ac131313@cygnus.com Sat Jun 03 04:48:00 2000
From: Andrew Cagney <ac131313@cygnus.com>
To: Kevin Buettner <kevinb@cygnus.com>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Sat, 03 Jun 2000 04:48:00 -0000
Message-id: <3938F055.42A9FEA3@cygnus.com>
References: <1000602075018.ZM29997@ocotillo.lan>
X-SW-Source: 2000-06/msg00031.html
Content-length: 747
Kevin Buettner wrote:
>
> As many of you know, I'm in the midst of purging the use of ``PARAMS''
> in prototyped function declarations from the gdb sources. After this
> activity is concluded, I'd like to begin converting function
> definitions whose parameters are declared using the traditional C
> style to the ISO C prototyped form. I.e, I'd like to convert
> functions of the form
Something to consider with the timing. There are Pascal, ObjectiveC.*
and random other Apple files pending. It might be good to wait until
the buil of the work is in the repository so that we reduce the number
of contributors / maintainers that get hit for six by this one :-)
Unlike params, this one will really hurt people with private diffs.
Andrew
From ac131313@cygnus.com Sat Jun 03 04:52:00 2000
From: Andrew Cagney <ac131313@cygnus.com>
To: Kevin Buettner <kevinb@cygnus.com>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Sat, 03 Jun 2000 04:52:00 -0000
Message-id: <3938F161.943C45F2@cygnus.com>
References: <1000602075018.ZM29997@ocotillo.lan> <3937816C.E66B9AE0@cygnus.com> <1000603072049.ZM32430@ocotillo.lan>
X-SW-Source: 2000-06/msg00032.html
Content-length: 511
Kevin Buettner wrote:
>
> On Jun 2, 7:42pm, Andrew Cagney wrote:
>
> > PS: You may want to add gdb/*-share to the list of directories to avoid.
>
> I can certainly do this, but I'd like to know why they shouldn't be
> converted...
Some of the *-share files are based on code from third parties. We
should probably try to avoid munging that code - it will make it harder
for us merge back patches. rdi-share comes to mind.
As you note, the TUI which will be cleaned up, can be handed separatly.
Andrew
From ac131313@cygnus.com Sat Jun 03 05:17:00 2000
From: Andrew Cagney <ac131313@cygnus.com>
To: jtc@redback.com
Cc: Kevin Buettner <kevinb@cygnus.com>, Mark Kettenis <kettenis@wins.uva.nl>, gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Sat, 03 Jun 2000 05:17:00 -0000
Message-id: <3938F700.509FD4AA@cygnus.com>
References: <1000602075018.ZM29997@ocotillo.lan> <200006021226.e52CQ2I01239@delius.kettenis.local> <1000602151553.ZM30578@ocotillo.lan> <5mya4om115.fsf@jtc.redback.com>
X-SW-Source: 2000-06/msg00033.html
Content-length: 1164
"J.T. Conklin" wrote:
>
> >>>>> "Kevin" == Kevin Buettner <kevinb@cygnus.com> writes:
> Kevin> I noticed that. The space was put there by ``indent''. I
> Kevin> would very much like to get rid of that space and it would be
> Kevin> easy to make the perl script postprocess the ``indent'' output.
> Kevin> But in doing so, we (obviously) generate different output than
> Kevin> that of ``indent''.
> Kevin>
> Kevin> I suppose the other solution is to fix indent. :-)
>
> You can tell indent about all the types defined by typedef with -T
> option, and then it won't add the extra space. It shouldn't be too
> difficult to identify all the types.
>
> It might be useful for us to maintain an indent.pro file that has
> these definitions so that additional runs of indent don't add back
> the space.
Given that people are currently editing headers to remove spaces by hand
this sounds like a good idea. One thing, how does one pass
``indent.pro'' rather than have it pick up ``.indent.pro''? I suspect
it can be maintained largely by hand (please not another perl script to
maintain it - we can't make perl a requirement on developers :-)
enjoy,
Andrew
From kevinb@cygnus.com Sat Jun 03 10:50:00 2000
From: Kevin Buettner <kevinb@cygnus.com>
To: Eli Zaretskii <eliz@is.elta.co.il>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Sat, 03 Jun 2000 10:50:00 -0000
Message-id: <1000603175039.ZM738@ocotillo.lan>
References: <200006021539.LAA25912@texas.cygnus.com> <1000602191042.ZM30936@ocotillo.lan> <200006031058.GAA12885@indy.delorie.com> <eliz@delorie.com>
X-SW-Source: 2000-06/msg00034.html
Content-length: 1970
On Jun 3, 6:58am, Eli Zaretskii wrote:
> So with a script, we will always need a verification tool that can be
> trusted to find any potential bugs introduced by reformatting.
Right.
That's why I wrote check-decls (see
http://sourceware.cygnus.com/ml/gdb/2000-06/msg00028.html
) which takes the result of comparing (via diff -u) the original
sources with the protoized sources and produces a C source file in
which the portions from the protoized sources are used to construct
prototypes and the portions from the original sources are used to
construct (potentially?) corresponding function definitions. We can
then invoke the C compiler (gcc -c -Wall) on the result and see what
kinds of warnings and errors are produced.
E.g, in an earlier (than the one I posted) version of fix-decls,
I hadn't yet handled comma separated parameter lists and so the
following:
foo (a, b, c)
int a;
char *b, *c;
was getting transformed into
foo (int a, int b, char *b, *c)
This type of mistake would've been quickly caught by check-decls +
gcc. (As it was, I caught it myself because I was looking for it.)
Also, since my fix-decls script merely looks for patterns which
appear to be function definitions, it was finding
if (overload_debug)
{
in find_overload_match() in valops.c and turning this into
if (int overload_debug)
{
(Note that the ``if'' is at the beginning of the line in this function.)
I found this one when I did a test build, but check-decls + the C
compiler would have caught this one too. (fix-decls was quickly
changed so that it no longer gets tripped up by this code.) Also, note
that check-decls would've caught this mistake even if the the
construct in question had appeared in some #if 0'd code whereas doing
a build wouldn't have.
I think it could still happen that something might slip by that won't
work in the real code, but now that I've written check-decls, I think
it is much, much less likely.
Kevin
From eliz@delorie.com Sat Jun 03 11:37:00 2000
From: Eli Zaretskii <eliz@delorie.com>
To: kevinb@cygnus.com
Cc: gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Sat, 03 Jun 2000 11:37:00 -0000
Message-id: <200006031837.OAA13278@indy.delorie.com>
References: <200006021539.LAA25912@texas.cygnus.com> <1000602191042.ZM30936@ocotillo.lan> <200006031058.GAA12885@indy.delorie.com> <1000603175039.ZM738@ocotillo.lan>
X-SW-Source: 2000-06/msg00035.html
Content-length: 870
> Date: Sat, 3 Jun 2000 10:50:39 -0700
> From: Kevin Buettner <kevinb@cygnus.com>
>
> That's why I wrote check-decls (see
> http://sourceware.cygnus.com/ml/gdb/2000-06/msg00028.html
> ) which takes the result of comparing (via diff -u) the original
> sources with the protoized sources and produces a C source file in
> which the portions from the protoized sources are used to construct
> prototypes and the portions from the original sources are used to
> construct (potentially?) corresponding function definitions. We can
> then invoke the C compiler (gcc -c -Wall) on the result and see what
> kinds of warnings and errors are produced.
I saw that script, but I don't like the idea to depend on a human to
judge what GCC warnings are okay to ignore and what aren't. I'd
prefer an automated tool that would give a definite yes/no answer, if
that's possible.
From pavenis@latnet.lv Sat Jun 03 11:47:00 2000
From: Andris Pavenis <pavenis@latnet.lv>
To: gdb@sourceware.cygnus.com
Cc: linux-kernel@vger.rutgers.edu
Subject: Problems with GDB-5.0 and recent Linux kernels (2.4.0-test1-ac[47])
Date: Sat, 03 Jun 2000 11:47:00 -0000
Message-id: <00060320465900.00261@hal>
X-SW-Source: 2000-06/msg00036.html
Content-length: 2559
Have somebody tried GDB commands 'info float' and 'info reg' on a system
running latest ac kernels. I'm getting coredump from gdb-5.0 on these commands.
2.4.0-test1 - seems that all works, no such problem
2.4.0-test1-ac4 and 2.4.0-test1-ac7 - gdb coredumps on these commands
It seems to be some stack corruption.
Andris
hal:/usr/src/build/gdb$ gdb gdb
GNU gdb 5.0
Copyright 2000 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "i386-slackware-linux"...
Setting up the environment for debugging gdb.
Breakpoint 1 at 0x80bf9cd: file ../../gdb-5.0/gdb/utils.c, line 723.
Breakpoint 2 at 0x80bd3af: file ../../gdb-5.0/gdb/top.c, line 2953.
Breakpoint 3 at 0x80a0563: file ../../gdb-5.0/gdb/i386-linux-nat.c, line 522.
(top-gdb) r
Starting program: /usr/src/build/gdb/gdb
GNU gdb 5.0
Copyright 2000 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "i586-pc-linux-gnu".
Setting up the environment for debugging gdb.
.gdbinit:5: Error in sourced command file:
No symbol table is loaded. Use the "file" command.
(gdb) file test1
Reading symbols from test1...done.
(gdb) tb main
Breakpoint 1 at 0x80485d6: file test1.c, line 10.
(gdb) r
Starting program: /usr/src/build/gdb/test1
main () at test1.c:10
10 rc = system ("ls -l");
(gdb) info float
Breakpoint 3, fetch_fpregs (tid=319) at ../../gdb-5.0/gdb/i386-linux-nat.c:522
522 if (ret < 0)
(top-gdb) n
528 supply_fpregset (&fpregs);
(top-gdb) n
529 }
(top-gdb)
fetch_inferior_registers (regno=Cannot access memory at address 0xffff0008
) at ../../gdb-5.0/gdb/i386-linux-nat.c:824
824 dummy_sse_values ();
(top-gdb)
825 return;
(top-gdb)
830 }
(top-gdb)
Program received signal SIGSEGV, Segmentation fault.
0x80a06c9 in fetch_inferior_registers (regno=Cannot access memory at address 0xffff0008
) at ../../gdb-5.0/gdb/i386-linux-nat.c:830
830 }
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Proposal: convert function definitions to prototyped form
2000-06-12 18:10 ` Andrew Cagney
@ 2000-06-12 19:48 ` Kevin Buettner
0 siblings, 0 replies; 5+ messages in thread
From: Kevin Buettner @ 2000-06-12 19:48 UTC (permalink / raw)
To: Andrew Cagney; +Cc: gdb
On Jun 13, 11:09am, Andrew Cagney wrote:
> Kevin Buettner wrote:
> >
> > As many of you know, I'm in the midst of purging the use of ``PARAMS''
> > in prototyped function declarations from the gdb sources. After this
> > activity is concluded, I'd like to begin converting function
> > definitions whose parameters are declared using the traditional C
> > style to the ISO C prototyped form. I.e, I'd like to convert
> > functions of the form
>
> Kevin,
>
> Would a fair summary of this be that you've encountered the following
> road blocks:
>
> o indent.pro
>
> So that indent gives better results
I don't think this is a serious road block. While it would be nice to
be able to specify an indent.pro file (e.g., "indent --options-file
gdbtypes.pro"), it's not absolutely necessary for the task at hand.
As I noted in my reply to Eric, I already know the complete list of
types which indent has to know about in order to complete the
protoization task. It is easy to put this list in the script which
does the conversion. I.e,
@typelist = qw(ADDR32 B_TYPE ... value_ptr xdrproc_t);
$indentoptions = '-T ' . join(' -T ', @typelist);
> o a drain of some of the backlog of
> patches (pascal I believe is now
> going in).
>
> Apple and HP?
I think the patch backlog is the real road block.
However, even for this road block, the only reason for delaying the
protoization activity is to make it easier on the people doing the
patch integration. Perhaps setting a date for the protoization
activity would help motivate the patch integrators to clear some of
the backlog?
> No one has objected to the principal (well not on gdb-patches :-) and
> the tool would be based on perl rather than the the gcc thing.
>
> Once those blockages are cleared, it can be scheduled and can go
> through?
I still have a little over a week to go on the PARAMS elimination
activity, so any time after then is good for me. How does midnight
GMT of Sunday July 9 sound? That's about four weeks away. Is that
enough time for the patch integrators to clear the patch backlog?
From eliz@delorie.com Tue Jun 13 03:34:00 2000
From: Eli Zaretskii <eliz@delorie.com>
To: ebachalo@redhat.com
Cc: jtc@redback.com, kevinb@cygnus.com, kettenis@wins.uva.nl, gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Tue, 13 Jun 2000 03:34:00 -0000
Message-id: <200006131034.GAA25579@indy.delorie.com>
References: <1000602075018.ZM29997@ocotillo.lan> <200006021226.e52CQ2I01239@delius.kettenis.local> <1000602151553.ZM30578@ocotillo.lan> <5mya4om115.fsf@jtc.redback.com> <394572A4.EF8646F2@redhat.com>
X-SW-Source: 2000-06/msg00117.html
Content-length: 209
> Date: Mon, 12 Jun 2000 16:30:44 -0700
> From: Eric Bachalo <ebachalo@redhat.com>
>
> Not sure how ported etags and python are for all the hosts that
> compile GDB though.
What platforms cause your concern?
From dcroyle@telerama.com Tue Jun 13 09:06:00 2000
From: David J Croyle <dcroyle@telerama.com>
To: gdb@sourceware.cygnus.com
Subject: Using GDB with standalone assembly code questions
Date: Tue, 13 Jun 2000 09:06:00 -0000
Message-id: <39466A96.E7B022BD@telerama.com>
X-SW-Source: 2000-06/msg00118.html
Content-length: 3164
Hello all!
We are trying to debug/verify a very simple ARM assembly language
program
and we hoped to use the gdb ARM simulator w/ddd as the frontend though
we
have encountered a few issues.
Our goal is to single step through the code and watch the registers
change
(and perhaps observe memory locations/memory mapped registers) but gdb
seems some what intent on not simulating our code.
We use the following sequence to "get gdb going":
(Load an ARM executable into gdb via DDD Open Program under File):
(gdb) file testarmasm.exec
warning: arm architecture file may be incompatible with armv4 target.
Reading symbols from
testarmasm.exec
(no debugging symbols found)...done.
We then issued these commands to gdb by hand:
(gdb) target sim
Connected to the simulator.
(gdb) set language asm
(gdb) load
Loading section .text, size 0x124 vma 0x0
Start address 0x0
Transfer rate: 2336 bits in <1 sec.
However when we issue the step command the response is:
(gdb) step
Single stepping until exit from function _start,
which has no line number information.
The program is not being run
Our registers don't change and neither does the program counter.
When we issue "run" gdb seems to get stuck in a never ending loop (the
registers which we have told ddd to display do not change) and the green
light just keeps blinking.
If we interrupt gdb and start the whole process over (reload the
executable, issue target sim, etc.) and use the "go" command and specify
a
label from our code such as ledon23(a valid label) our response is:
(gdb) go ledon23
Breakpoint 1 at 0xa8
Continuing at 0xa8.
The program is not being run.
(gdb)
We then see the program counter pointing to 0xa8 but issuing "run"
either
locks gdb or if we stop the run almost imediatly with control-c, we can
see that a few registers changed though the run/interruption cannot be
done with any hopes of reliability.
It is interesting to note that while gdb mentions it did not find any
debug symbols, it does know of the labels we used in our ASM program
meaning it has read that information successfully from our executable.
In addition to the run/control-c, we can issue a "b <label>" and gdb
will
set the breakpoint at the correct label (the address was verified by
looking out our .lst file). However we still do not have the ability to
single step/step into the next instruction.
An "info watchpoints" shows all our breakpoints with the correct labels.
Are there any suggestions on how we can single step through our code or
execute our "pure ASM" program and observe registers and such?
We've built gdb for target=strongarm-elf on a i686-pc-linux-gnu host.
We've told ddd to use our strongarm built gdb by using the --debugger
switch on ddd start-up.
Our ARM executable was built on this same machine, cross-compiled by
using
a cross toolchain we built to produce standalone ARM executables (we
used
newlib headers instead of glibc but since this is "pure ASM" program
that
should not matter).
Thanks in advance,
Dave & Vasant.
David J. Croyle
EE / Software Developer
Foerster Instruments, Inc.
Windows e-mail: dcroyle@foerstergroup.com
Linux e-mail: dcroyle@telerama.com
From fnasser@cygnus.com Tue Jun 13 10:02:00 2000
From: Fernando Nasser <fnasser@cygnus.com>
To: David J Croyle <dcroyle@telerama.com>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Using GDB with standalone assembly code questions
Date: Tue, 13 Jun 2000 10:02:00 -0000
Message-id: <394668A0.7C8B3DA2@cygnus.com>
References: <39466A96.E7B022BD@telerama.com>
X-SW-Source: 2000-06/msg00119.html
Content-length: 3829
David,
First of all, which compiler and which version of it have you used?
The exact compile line, with all switches is also necessary.
Then you should tell us which gdb (version, where did you get it etc.)
you are using.
Fernando
David J Croyle wrote:
>
> Hello all!
>
> We are trying to debug/verify a very simple ARM assembly language
> program
> and we hoped to use the gdb ARM simulator w/ddd as the frontend though
> we
> have encountered a few issues.
>
> Our goal is to single step through the code and watch the registers
> change
> (and perhaps observe memory locations/memory mapped registers) but gdb
> seems some what intent on not simulating our code.
>
> We use the following sequence to "get gdb going":
>
> (Load an ARM executable into gdb via DDD Open Program under File):
>
> (gdb) file testarmasm.exec
> warning: arm architecture file may be incompatible with armv4 target.
> Reading symbols from
> testarmasm.exec
> (no debugging symbols found)...done.
>
> We then issued these commands to gdb by hand:
>
> (gdb) target sim
> Connected to the simulator.
> (gdb) set language asm
> (gdb) load
> Loading section .text, size 0x124 vma 0x0
> Start address 0x0
> Transfer rate: 2336 bits in <1 sec.
>
> However when we issue the step command the response is:
>
> (gdb) step
> Single stepping until exit from function _start,
> which has no line number information.
> The program is not being run
>
> Our registers don't change and neither does the program counter.
>
> When we issue "run" gdb seems to get stuck in a never ending loop (the
> registers which we have told ddd to display do not change) and the green
> light just keeps blinking.
>
> If we interrupt gdb and start the whole process over (reload the
> executable, issue target sim, etc.) and use the "go" command and specify
> a
> label from our code such as ledon23(a valid label) our response is:
>
> (gdb) go ledon23
> Breakpoint 1 at 0xa8
> Continuing at 0xa8.
> The program is not being run.
> (gdb)
>
> We then see the program counter pointing to 0xa8 but issuing "run"
> either
> locks gdb or if we stop the run almost imediatly with control-c, we can
> see that a few registers changed though the run/interruption cannot be
> done with any hopes of reliability.
>
> It is interesting to note that while gdb mentions it did not find any
> debug symbols, it does know of the labels we used in our ASM program
> meaning it has read that information successfully from our executable.
>
> In addition to the run/control-c, we can issue a "b <label>" and gdb
> will
> set the breakpoint at the correct label (the address was verified by
> looking out our .lst file). However we still do not have the ability to
> single step/step into the next instruction.
>
> An "info watchpoints" shows all our breakpoints with the correct labels.
>
> Are there any suggestions on how we can single step through our code or
> execute our "pure ASM" program and observe registers and such?
>
> We've built gdb for target=strongarm-elf on a i686-pc-linux-gnu host.
> We've told ddd to use our strongarm built gdb by using the --debugger
> switch on ddd start-up.
>
> Our ARM executable was built on this same machine, cross-compiled by
> using
> a cross toolchain we built to produce standalone ARM executables (we
> used
> newlib headers instead of glibc but since this is "pure ASM" program
> that
> should not matter).
>
> Thanks in advance,
> Dave & Vasant.
>
> David J. Croyle
> EE / Software Developer
> Foerster Instruments, Inc.
> Windows e-mail: dcroyle@foerstergroup.com
> Linux e-mail: dcroyle@telerama.com
--
Fernando Nasser
Red Hat Canada Ltd. E-Mail: fnasser@cygnus.com
2323 Yonge Street, Suite #300 Tel: 416-482-2661 ext. 311
Toronto, Ontario M4P 2C9 Fax: 416-482-6299
From jtc@redback.com Tue Jun 13 15:19:00 2000
From: jtc@redback.com (J.T. Conklin)
To: gdb@sourceware.cygnus.com
Subject: nindy protocol
Date: Tue, 13 Jun 2000 15:19:00 -0000
Message-id: <5mbt155ino.fsf@jtc.redback.com>
X-SW-Source: 2000-06/msg00120.html
Content-length: 1697
Does anyone have a copy of the Nindy protocol specification or an old
Intel gnu960 (aka CTOOLS) distribution that contains Nindy source? I
checked developer.intel.com, but the CTOOLS distributions currently
available all have mon960 instead of Nindy.
The reason I ask is because I'd like to get rid of the dcache_fetch()
and dcache_poke() functions which are only used by remote-nindy.c and
remote-bug.c.
Unlike most remote targets, the nindy_xfer_inferior_memory() function
breaks the transfer into multiple word-aligned word-sized transfers.
These word-sized transfers are performed through dcache_fetch() and
dcache_poke(). The header comment for nindy_xfer_inferior_memory()
states:
"This is stolen almost directly from infptrace.c's
child_xfer_memory, which also deals with a word-oriented
memory interface. Sometime, FIXME, rewrite this to not use
the word-oriented routines."
I'm not sure whether this means that nindy protocol supports non-word-
aligned, non-word-sized transfers, and the code just needs to be fixed
to use them, or if something more substantial must be done. I checked
the code in nindy-share/nindy.c, which seems to indicate that the
protocol supports arbitrary sized/aligned transfers, but it's not
explicitly stated. I'd like to confirm this before submitting a patch.
In case anyones wondering, the primary reason I'd like to get rid of
these functions is that otherwise I'd have to adapt them to take a
mem_attrib parameter. They also seem to be poorly specified. They
read and write a host word, when I'd think they would be defined in
terms of the target's word size.
--jtc
--
J.T. Conklin
RedBack Networks
From shebs@apple.com Tue Jun 13 16:25:00 2000
From: Stan Shebs <shebs@apple.com>
To: jtc@redback.com
Cc: gdb@sourceware.cygnus.com
Subject: Re: nindy protocol
Date: Tue, 13 Jun 2000 16:25:00 -0000
Message-id: <3946C259.3F4C058A@apple.com>
References: <5mbt155ino.fsf@jtc.redback.com>
X-SW-Source: 2000-06/msg00121.html
Content-length: 1124
"J.T. Conklin" wrote:
>
> Does anyone have a copy of the Nindy protocol specification or an old
> Intel gnu960 (aka CTOOLS) distribution that contains Nindy source? I
> checked developer.intel.com, but the CTOOLS distributions currently
> available all have mon960 instead of Nindy.
I squirreled away a couple copies of CTOOLs when I was at Cygnus, but
I don't know if any were old enough to include Nindy sources still;
don't remember ever seeing actual Nindy sources.
> The reason I ask is because I'd like to get rid of the dcache_fetch()
> and dcache_poke() functions which are only used by remote-nindy.c and
> remote-bug.c.
IMHO we should officially declare Nindy support obsolete. As you observed,
Intel now denies its existence :-), the last physical board I knew of
(at Cygnus) died ca 1996, and the last couple of years of GDB churning
probably broke the Nindy support, but nobody appears to have noticed,
or cared enough to report it as a bug.
I could do the research to justify obsoleting Nindy, then you'd be free
to whack the dcache functions (remote-bug.c is also an obsoletion
possibility BTW).
Stan
From ac131313@cygnus.com Tue Jun 13 18:32:00 2000
From: Andrew Cagney <ac131313@cygnus.com>
To: David J Croyle <dcroyle@telerama.com>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Using GDB with standalone assembly code questions
Date: Tue, 13 Jun 2000 18:32:00 -0000
Message-id: <3946E059.266C39A3@cygnus.com>
References: <39466A96.E7B022BD@telerama.com>
X-SW-Source: 2000-06/msg00122.html
Content-length: 339
David J Croyle wrote:
> (gdb) step
> Single stepping until exit from function _start,
> which has no line number information.
> The program is not being run
FYI, several things to be careful about.
Use stepi not step.
You may need to do a:
(gdb) break *_start
or is that break *&_start?
(gdb) run
to get things started.
Andrew
From jtc@redback.com Tue Jun 13 18:54:00 2000
From: jtc@redback.com (J.T. Conklin)
To: Stan Shebs <shebs@apple.com>
Cc: gdb@sourceware.cygnus.com
Subject: Re: nindy protocol
Date: Tue, 13 Jun 2000 18:54:00 -0000
Message-id: <5mg0qh3u4o.fsf@jtc.redback.com>
References: <5mbt155ino.fsf@jtc.redback.com> <3946C259.3F4C058A@apple.com>
X-SW-Source: 2000-06/msg00123.html
Content-length: 2235
>>>>> "Stan" == Stan Shebs <shebs@apple.com> writes:
Stan> I squirreled away a couple copies of CTOOLs when I was at Cygnus, but
Stan> I don't know if any were old enough to include Nindy sources still;
Stan> don't remember ever seeing actual Nindy sources.
Do you still have access to them? I found the CTOOLS 5.0 release
notes on developer.intel.com --- it looks like Nindy was replaced
then. If you have an earlier release, it should have the Nindy
sources.
>> The reason I ask is because I'd like to get rid of the dcache_fetch()
>> and dcache_poke() functions which are only used by remote-nindy.c and
>> remote-bug.c.
Stan> IMHO we should officially declare Nindy support obsolete. As
Stan> you observed, Intel now denies its existence :-), the last
Stan> physical board I knew of (at Cygnus) died ca 1996, and the last
Stan> couple of years of GDB churning probably broke the Nindy
Stan> support, but nobody appears to have noticed, or cared enough to
Stan> report it as a bug.
Stan> I could do the research to justify obsoleting Nindy, then you'd
Stan> be free to whack the dcache functions (remote-bug.c is also an
Stan> obsoletion possibility BTW).
Feel free. I'm not going to argue against it. However, if Nindy
supports arbitrary sized and aligned memory transfers the changes
necessary to remove dcache_fetch() and dcache_poke() are trivial. If
we can't determine whether it's safe, and you want to wait more before
obsoleting the config, I propose that we commit it anyway. If it
breaks anything and anyone cares, we'll hear about it soon enough.
It appears that the remote-bug.c implements read/write by downloading
and uploading s-records, so there should be no problems at all removing
dcache_fetch() and dcache_poke() from it (at least I've never heard of
any srec reader that didn't support arbitrary addresses).
If the MVME187BUG monitor is anything like the m68k, ppc, and coldfire
versions of BUG, it could be rewritten to use the generic monitor code,
resulting in a smaller and more robust target. Whether anyone cares to
do so is another story. If remote-bug.c is obsoleted, it appears that
most of remote-utils.c (all the gr_* stuff) can too.
--jtc
--
J.T. Conklin
RedBack Networks
From shebs@apple.com Tue Jun 13 20:20:00 2000
From: Stan Shebs <shebs@apple.com>
To: jtc@redback.com
Cc: gdb@sourceware.cygnus.com
Subject: Re: nindy protocol
Date: Tue, 13 Jun 2000 20:20:00 -0000
Message-id: <3946F992.4A40BA12@apple.com>
References: <5mbt155ino.fsf@jtc.redback.com> <3946C259.3F4C058A@apple.com> <5mg0qh3u4o.fsf@jtc.redback.com>
X-SW-Source: 2000-06/msg00124.html
Content-length: 1822
"J.T. Conklin" wrote:
>
> >>>>> "Stan" == Stan Shebs <shebs@apple.com> writes:
> Stan> I squirreled away a couple copies of CTOOLs when I was at Cygnus, but
> Stan> I don't know if any were old enough to include Nindy sources still;
> Stan> don't remember ever seeing actual Nindy sources.
>
> Do you still have access to them? I found the CTOOLS 5.0 release
> notes on developer.intel.com --- it looks like Nindy was replaced
> then. If you have an earlier release, it should have the Nindy
> sources.
Actually, I think 5.0 is the earliest I have too.
> Stan> I could do the research to justify obsoleting Nindy, then you'd
> Stan> be free to whack the dcache functions (remote-bug.c is also an
> Stan> obsoletion possibility BTW).
>
> Feel free. I'm not going to argue against it. However, if Nindy
> supports arbitrary sized and aligned memory transfers the changes
> necessary to remove dcache_fetch() and dcache_poke() are trivial. If
> we can't determine whether it's safe, and you want to wait more before
> obsoleting the config, I propose that we commit it anyway. If it
> breaks anything and anyone cares, we'll hear about it soon enough.
Fine by me.
> If the MVME187BUG monitor is anything like the m68k, ppc, and coldfire
> versions of BUG, it could be rewritten to use the generic monitor code,
> resulting in a smaller and more robust target. Whether anyone cares to
> do so is another story.
There was at least one m88k workstation alive recently, somebody on this
whose name I forget (sorry) sent in some patches for it last year or so.
But embedded m88k boards these days? Rather unlikely I think.
> If remote-bug.c is obsoleted, it appears that
> most of remote-utils.c (all the gr_* stuff) can too.
Yup, an attractive side benefit. To borrow from S&W, "omit needless code". :-)
Stan
From qqi@world.std.com Wed Jun 14 05:50:00 2000
From: Quality Quorum <qqi@world.std.com>
To: Andrew Cagney <ac131313@cygnus.com>
Cc: GDB Discussion <gdb@sourceware.cygnus.com>
Subject: Re: That vision thing ...
Date: Wed, 14 Jun 2000 05:50:00 -0000
Message-id: <Pine.SGI.3.95.1000614084827.13939A-100000@world.std.com>
References: <39457E1A.D22C6468@cygnus.com>
X-SW-Source: 2000-06/msg00125.html
Content-length: 390
On Tue, 13 Jun 2000, Andrew Cagney wrote:
> So yes.
>
> Exactly how to do this is another problem entirely. Do we just
> re-arange the deck chairs or look more deeply.
I would say re-arranging of deck chairs will be a signficant help
in the looking, especially for the guys like me who mostly uses
gdb and seldom has to tweak pieces here and there.
>
> Andrew
>
Thanks,
Aleksey
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Proposal: convert function definitions to prototyped form
[not found] <1000602075018.ZM29997@ocotillo.lan>
2000-06-02 5:26 ` Proposal: convert function definitions to prototyped form Mark Kettenis
[not found] ` <3937816C.E66B9AE0@cygnus.com>
@ 2000-06-12 18:10 ` Andrew Cagney
2000-06-12 19:48 ` Kevin Buettner
2 siblings, 1 reply; 5+ messages in thread
From: Andrew Cagney @ 2000-06-12 18:10 UTC (permalink / raw)
To: Kevin Buettner; +Cc: gdb
Kevin Buettner wrote:
>
> As many of you know, I'm in the midst of purging the use of ``PARAMS''
> in prototyped function declarations from the gdb sources. After this
> activity is concluded, I'd like to begin converting function
> definitions whose parameters are declared using the traditional C
> style to the ISO C prototyped form. I.e, I'd like to convert
> functions of the form
Kevin,
Would a fair summary of this be that you've encountered the following
road blocks:
o indent.pro
So that indent gives better results
o a drain of some of the backlog of
patches (pascal I believe is now
going in).
Apple and HP?
No one has objected to the principal (well not on gdb-patches :-) and
the tool would be based on perl rather than the the gcc thing.
Once those blockages are cleared, it can be scheduled and can go
through?
Andrew
From shebs@apple.com Mon Jun 12 18:15:00 2000
From: Stan Shebs <shebs@apple.com>
To: Daniel Berlin <dan@cgsoftware.com>
Cc: Andrew Cagney <ac131313@cygnus.com>, Eric Bachalo <ebachalo@redhat.com>, gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Mon, 12 Jun 2000 18:15:00 -0000
Message-id: <39458A9E.239C8A81@apple.com>
References: <Pine.LNX.4.10.10006121802590.29924-100000@propylaea.anduin.com>
X-SW-Source: 2000-06/msg00103.html
Content-length: 374
Daniel Berlin wrote:
>
> Funny you guys bring up the number of types in GDB.
> According to the debug info, there are >82,000.
> How exactly are we counting them, again?
Since GDB sources are around 400K lines or so, it's highly unlikely
that there is a type definition for every five lines in the
C sources. You're seeing duplicates in the debug info, presumably.
Stan
From dan@cgsoftware.com Mon Jun 12 18:23:00 2000
From: Daniel Berlin <dan@cgsoftware.com>
To: Stan Shebs <shebs@apple.com>
Cc: Andrew Cagney <ac131313@cygnus.com>, Eric Bachalo <ebachalo@redhat.com>, gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Mon, 12 Jun 2000 18:23:00 -0000
Message-id: <Pine.LNX.4.10.10006121815430.29924-100000@propylaea.anduin.com>
References: <39458A9E.239C8A81@apple.com>
X-SW-Source: 2000-06/msg00104.html
Content-length: 643
Before my patches to eliminate duplicate dwarf2 info, it said there were
120k.
So something isn't adding up here.
I find it hard to believe we duplicate that much info.
It's pretty much absurd.
--Dan
On Mon, 12 Jun 2000, Stan Shebs wrote:
> Daniel Berlin wrote:
> >
> > Funny you guys bring up the number of types in GDB.
> > According to the debug info, there are >82,000.
> > How exactly are we counting them, again?
>
> Since GDB sources are around 400K lines or so, it's highly unlikely
> that there is a type definition for every five lines in the
> C sources. You're seeing duplicates in the debug info, presumably.
>
> Stan
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Proposal: convert function definitions to prototyped form
[not found] ` <3938F700.509FD4AA@cygnus.com>
@ 2000-06-05 11:05 ` J.T. Conklin
0 siblings, 0 replies; 5+ messages in thread
From: J.T. Conklin @ 2000-06-05 11:05 UTC (permalink / raw)
To: Andrew Cagney; +Cc: Kevin Buettner, Mark Kettenis, gdb
>>>>> "Andrew" == Andrew Cagney <ac131313@cygnus.com> writes:
Andrew> Given that people are currently editing headers to remove
Andrew> spaces by hand this sounds like a good idea. One thing, how
Andrew> does one pass ``indent.pro'' rather than have it pick up
Andrew> ``.indent.pro''? I suspect it can be maintained largely by
Andrew> hand (please not another perl script to maintain it - we can't
Andrew> make perl a requirement on developers :-)
For what we want to do, indent needs an option to disable processing
the .indent.pro files located in the current or home directories, and
another to process an arbitrary file. I examined the latest revision
of the indent sources, 2.2.5, and I can not find an option to process
a file containing options.
It appears that indent is being actively maintained. Perhaps someone
with a bit of time on their hands can work with the indent maintainer
to get such an option in a future revesion.
--jtc
--
J.T. Conklin
RedBack Networks
From kettenis@wins.uva.nl Mon Jun 05 11:54:00 2000
From: Mark Kettenis <kettenis@wins.uva.nl>
To: ac131313@cygnus.com
Cc: gdb@sourceware.cygnus.com, shebs@apple.com, fnasser@cygnus.com
Subject: Re: 5.0 post mortem
Date: Mon, 05 Jun 2000 11:54:00 -0000
Message-id: <200006051853.e55IriS09643@delius.kettenis.local>
References: <393B16D9.E217DAA1@cygnus.com>
X-SW-Source: 2000-06/msg00043.html
Content-length: 548
Date: Mon, 05 Jun 2000 12:56:25 +1000
From: Andrew Cagney <ac131313@cygnus.com>
Well before a 5.0.1 or 5.1 release is started its probably worth having
a bit of a post-mortem (where the vultures can pick over the bones of
what happened :-) Here are my random thoughts:
[snip]
o we need more tests
Here's a test for the x86 SIGALRM problem that's still listed in the
TODO file to remind us of adding it. Looks like it's falling through
the cracks:
http://sourceware.cygnus.com/ml/gdb-patches/2000-05/msg00309.html
Mark
From dan@cgsoftware.com Mon Jun 05 13:51:00 2000
From: Daniel Berlin <dan@cgsoftware.com>
To: gdb-patches@sourcware.cygnus.com
Cc: gdb@sourceware.cygnus.com
Subject: [FYI]: Incoming C++ changes
Date: Mon, 05 Jun 2000 13:51:00 -0000
Message-id: <Pine.LNX.4.10.10006051338440.29861-100000@propylaea.anduin.com>
X-SW-Source: 2000-06/msg00044.html
Content-length: 1002
I made quite a bunch of C++ improvements over the weekend (i was gone
until 3pm today), i'll be committing in a moment.
In no particular order:
1. Symbol table performance is vastly improved. No longer do we need to
force a linear search for C++, ever.
This required simply changing STREQ(SYMBOL_NAME,name)) to
SYMBOL_MATCHES_NAME. Once that was done, the issues that required doing
the linear search in the first place no longer occurred. This change
causes no regressions.
2. Template handling improvements. Should be as good as it is on HP now.
Required removing some code in the expression parser that was dupicating,
but doing less, than something that could already do it.
3. Test suite improvements: Tests we previously skipped on g++, we now
don't skip, and pass (particularly, template tests). I also added a
namespace test from the gdb.hp dir. This requirred changing a few tests to
accept valid output.
This actually exposes what appears to be a bug in demangling when you use
stabs.
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Proposal: convert function definitions to prototyped form
[not found] <1000602075018.ZM29997@ocotillo.lan>
@ 2000-06-02 5:26 ` Mark Kettenis
[not found] ` <1000602151553.ZM30578@ocotillo.lan>
[not found] ` <3937816C.E66B9AE0@cygnus.com>
2000-06-12 18:10 ` Andrew Cagney
2 siblings, 1 reply; 5+ messages in thread
From: Mark Kettenis @ 2000-06-02 5:26 UTC (permalink / raw)
To: kevinb; +Cc: gdb
Date: Fri, 2 Jun 2000 00:50:19 -0700
From: Kevin Buettner <kevinb@cygnus.com>
Comma separated list with differing number of stars on the parameter
names (sparc-tdep.c):
static branch_type
-isbranch (instruction, addr, target)
- long instruction;
- CORE_ADDR addr, *target;
+isbranch (long instruction, CORE_ADDR addr, CORE_ADDR * target)
{
I guess you should tweak it some more such that it outputs
CORE_ADDR *target
instead of
CORE_ADDR * target
(note the spurious space between * and target).
Mark
From kevinb@cygnus.com Fri Jun 02 08:16:00 2000
From: Kevin Buettner <kevinb@cygnus.com>
To: Mark Kettenis <kettenis@wins.uva.nl>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Fri, 02 Jun 2000 08:16:00 -0000
Message-id: <1000602151553.ZM30578@ocotillo.lan>
References: <1000602075018.ZM29997@ocotillo.lan> <200006021226.e52CQ2I01239@delius.kettenis.local> <kettenis@wins.uva.nl>
X-SW-Source: 2000-06/msg00016.html
Content-length: 997
On Jun 2, 2:26pm, Mark Kettenis wrote:
> Date: Fri, 2 Jun 2000 00:50:19 -0700
> From: Kevin Buettner <kevinb@cygnus.com>
>
> Comma separated list with differing number of stars on the parameter
> names (sparc-tdep.c):
>
> static branch_type
> -isbranch (instruction, addr, target)
> - long instruction;
> - CORE_ADDR addr, *target;
> +isbranch (long instruction, CORE_ADDR addr, CORE_ADDR * target)
> {
>
> I guess you should tweak it some more such that it outputs
>
> CORE_ADDR *target
>
> instead of
>
> CORE_ADDR * target
>
> (note the spurious space between * and target).
I noticed that. The space was put there by ``indent''. I would very
much like to get rid of that space and it would be easy to make the
perl script postprocess the ``indent'' output. But in doing so, we
(obviously) generate different output than that of ``indent''.
I suppose the other solution is to fix indent. :-)
FYI, I'm using GNU indent 2.2.5.
Kevin
From taylor@cygnus.com Fri Jun 02 08:40:00 2000
From: David Taylor <taylor@cygnus.com>
To: Kevin Buettner <kevinb@cygnus.com>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Fri, 02 Jun 2000 08:40:00 -0000
Message-id: <200006021539.LAA25912@texas.cygnus.com>
X-SW-Source: 2000-06/msg00017.html
Content-length: 4312
Date: Fri, 2 Jun 2000 00:50:19 -0700
From: Kevin Buettner <kevinb@cygnus.com>
[...]
2) ``protoize'' fails to convert functions disabled by ifdefs for
the given platform. OTOH, on some other platform(s), these
functions might not be disabled and would be converted. E.g,
in breakpoint.c, on my GNU/Linux/x86 machine, protoize failed
to convert create_longjmp_breakpoint() which is protected by an
"#ifdef GET_LONGJMP_TARGET".
With any solution, either you're going to have to check the results or
you're going to have to hand convert some of the stuff. It's a
tradeoff. From what you say below, your script also requires some
later hand conversions.
Does your script produce substantially less that needs to be hand
converted?
3) ``protoize'' screws up on PTR types. E.g, in breakpoint.c, it
converted
static int
cover_target_enable_exception_callback (arg)
PTR arg;
to
static int
cover_target_enable_exception_callback (__builtin_va_list arg)
I consider this to be a more serious problem than the other complaints
you have.
4) ``protoize'' does not reformat long argument lists. The lists
end up entirely contained on one line.
So... adopt the same solution for it that you chose to adopt for your
script -- run indent on the output!
For more information on protoize, see the "Running protoize" page:
http://gcc.gnu.org/onlinedocs/gcc_2.html#SEC48
and the "Caveats of using protoize" page:
http://gcc.gnu.org/onlinedocs/gcc_7.html#SEC135
I've used protoize before with good results. It was a fairly
substantial project, though not as big as gdb.
Two of my goals in creating the scripts for the PARAMS purging
activities was that the scripts should be 1) easy to invoke and 2)
require no hand editing of the output when done. I.e, you shouldn't
have to edit any of the files that these scripts touch in order to fix
I trust that "3)" is:
"be conservative; not convert something if it can't be sure
of getting it right".
I'd much rather hand convert more of the code than have it make a
subtle but incorrect change.
errors so that you can build again. OTOH, the script may leave
certain portions of the file alone that could possibly have be
converted had the script been a little smarter. The things that the
script fails to convert *will* have to be fixed later on (in order to
complete the cleanup activity), either by another script, or by hand.
For the PARAMS purging activity, I have spent a fair amount of time
examining the diffs to make sure that this is indeed the case. (And
I intend to do the same for the activity in this proposal.)
Good.
The reason that it is so important to avoid any hand edits is that we
want people who have local repositories or checked out source trees to
be able to run these conversion scripts against them so that merges
will be less painful. (Even easy.)
Agreed.
With that said, keeping in mind the problems I noted above, I conclude
that ``protoize'' is not the appropriate tool for us to use to convert
function definitions in the gdb sources to their prototyped form.
I only consider 3) -- screwing up on PTR types -- to be serious; the
others seem minor enough.
[...]
Finally, I should note that I've done a test build on GNU/Linux/x86
and had no build problems, nor did I see any regressions when I ran
the testsuite.
The fix-decls script is below. I'd be interested in finding out if
anyone else has a favorite script for doing this sort of thing. Other
comments welcome too.
I'd be tempted to do a build before running your script; stash away the
object files; run the script; do another build; compare the object
files...
I consider the lack of (prototyped) function declarations to be more
serious "problem" than the use of old style function definitions in
old code. I'd like to see:
. declarations near the top of every file (i.e., before the first
function definition) for every static function in the file.
. a declaration in an included header file for every non static
function definition and for every non static function used.
. changes to the default configuration to "encourage" developers to
include the above declarations.
From davea@quasar.engr.sgi.com Fri Jun 02 09:17:00 2000
From: davea@quasar.engr.sgi.com (David B Anderson)
To: gdb@sourceware.cygnus.com
Subject: Re: does GDB support IRIX 64 bit executables?
Date: Fri, 02 Jun 2000 09:17:00 -0000
Message-id: <200006021622.JAA05620@quasar.engr.sgi.com>
X-SW-Source: 2000-06/msg00018.html
Content-length: 952
On: irix 64 bit pointer apps and dwarf2 and gdb
robert somerville <somervil@cadvision.com>
writes:
>i got this patch from :
> Benjamin Gamsa <ben@eecg.toronto.edu>
The patch makes no distinction between address-size
and offset-size in the dwarf2, but that is
an essential distinction, I think.
I think the patch as written
will break alpha-64-bit-pointers-using-dwarf2 in dwarf2read.c
That is, it will break
any non-sgi target with 64bit pointers and dwarf2,
as *only* SGI extended offsets/lengths in dwarf2 to 64bits for
64bit pointer apps. And the patch makes no provision for
the coming dwarf2 revision with its compatible allowance
of 32-bit-offset and 64-bit-offset dwarf2 in a single
object file.
I believe this is very easily dealt with.
I hope to get to this to suggest a revised patch soon, but
of course, promises are worthless :-)
Regards,
David B. Anderson davea@sgi.com danderson@acm.org http://reality.sgi.com/davea/
From Will_Lentz@Trimble.COM Fri Jun 02 10:34:00 2000
From: Will Lentz <Will_Lentz@Trimble.COM>
To: Peter Reilley <micrio@mv.com>, gdb@sourceware.cygnus.com
Subject: RE: Questions on GDB
Date: Fri, 02 Jun 2000 10:34:00 -0000
Message-id: <8B0BE50D6F9AD01185A300A0C92BF455088393EE@US01XCH01.Trimble.COM>
X-SW-Source: 2000-06/msg00019.html
Content-length: 1327
Hi Pete,
For a remote PPC target (through rproxy), I use:
file xyz.elf
target remote ip.addr:port
load
run
It's really cool that you ported the Macraigor DLL to Linux! I
think more people would use the Wiggler if your port was made
available :-).
Will
> -----Original Message-----
> From: Peter Reilley [ mailto:micrio@mv.com ]
> Sent: Thursday, June 01, 2000 2:24 PM
> To: gdb@sourceware.cygnus.com
> Subject: Questions on GDB
>
>
> I have a few questions on the operation of GDB with the Wiggler
> and a PowerPC target.
>
> I have ported the Macraigor DLL from MS Windows to Linux and
> am attempting to get GDB working. I can read and write registers
> and memory in the PPC target. I have a small test program that
> I compiled with GCC configured as a cross compiler for the PPC.
> I can use the "load" command and have the binary load properly
> in the target memory. I can use the "symbol-file" command to
> load the symbols. The "file" command will load the binary but
> it seems to have a base address in the host and not the target.
> The "run" and "step" commands do not seem to work.
>
> Anyway, what are the commands that you used to load and execute
> a binary in a target under Windows. The documentation that I found
> on the internet is conflicting.
>
> Thanks,
> Pete.
>
>
>
>
>
From jtc@redback.com Fri Jun 02 10:44:00 2000
From: jtc@redback.com (J.T. Conklin)
To: Kevin Buettner <kevinb@cygnus.com>
Cc: Mark Kettenis <kettenis@wins.uva.nl>, gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Fri, 02 Jun 2000 10:44:00 -0000
Message-id: <5mya4om115.fsf@jtc.redback.com>
References: <1000602075018.ZM29997@ocotillo.lan> <200006021226.e52CQ2I01239@delius.kettenis.local> <1000602151553.ZM30578@ocotillo.lan>
X-SW-Source: 2000-06/msg00020.html
Content-length: 799
>>>>> "Kevin" == Kevin Buettner <kevinb@cygnus.com> writes:
Kevin> I noticed that. The space was put there by ``indent''. I
Kevin> would very much like to get rid of that space and it would be
Kevin> easy to make the perl script postprocess the ``indent'' output.
Kevin> But in doing so, we (obviously) generate different output than
Kevin> that of ``indent''.
Kevin>
Kevin> I suppose the other solution is to fix indent. :-)
You can tell indent about all the types defined by typedef with -T
option, and then it won't add the extra space. It shouldn't be too
difficult to identify all the types.
It might be useful for us to maintain an indent.pro file that has
these definitions so that additional runs of indent don't add back
the space.
--jtc
--
J.T. Conklin
RedBack Networks
From kevinb@cygnus.com Fri Jun 02 12:10:00 2000
From: Kevin Buettner <kevinb@cygnus.com>
To: David Taylor <taylor@cygnus.com>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Fri, 02 Jun 2000 12:10:00 -0000
Message-id: <1000602191042.ZM30936@ocotillo.lan>
References: <200006021539.LAA25912@texas.cygnus.com> <taylor@cygnus.com>
X-SW-Source: 2000-06/msg00021.html
Content-length: 7094
On Jun 2, 11:39am, David Taylor wrote:
> With any solution, either you're going to have to check the results or
> you're going to have to hand convert some of the stuff. It's a
> tradeoff. From what you say below, your script also requires some
> later hand conversions.
Yes. But, it's conservative in that it won't break your builds.
(Or at least that's the intent.)
> Does your script produce substantially less that needs to be hand
> converted?
I only ran protoize on breakpoint.c to see what the problems were.
This was the file that required the most conversion, however, so
hopefully it's a good representative sample. For this file, protoize
converted 126 function declarations and fix-decls converted 138. In
addition, not counting reformatting, the protoized version of
breakpoint.c would require 5 hand edits in order to fix problems
introduced in the conversion. The fix-decls version requires 0 hand
edits. After conversion, the protoized version of breakpoint.c
still had 15 functions which would need to be converted by hand (or
some other tool) whereas the fix-decls version had only 3. Here's
a table to summarizing the above:
breakpoint.c conversion
| protoize | fix-decls |
----------------------------------------------+----------+-----------+
Functions converted | 126 | 138 |
----------------------------------------------+----------+-----------+
Hand edits needed afterwards to fix problems | | |
in the conversion process | 5 | 0 |
----------------------------------------------+----------+-----------+
Functions remaining to be converted | 15 | 3 |
----------------------------------------------+----------+-----------+
Total number of hand edits required | 20 | 3 |
----------------------------------------------+----------+-----------+
Recall that over all of the gdb sources, fix-decls converted slightly
over 5200 declarations. I believe that there are only around 140 left
to consider. This is somewhat higher than I would like and I may be
able to reduce it somewhat by making the script a little bit smarter.
But I also want to be certain that no errors are introduced in the
process.
I should note that there are many settings where protoize is a
completely acceptable (and probably better) tool. With gdb, however,
we have a lot of developers scattered across the globe who need to be
able to deterministically apply the same transformations to their
sources in order to make merges and checkins easier.
With protoize, I think it's going be be difficult to guarantee
determinism since the results will vary depending upon which platform
you use to do the transformation.
> 3) ``protoize'' screws up on PTR types. E.g, in breakpoint.c, it
> converted
>
> static int
> cover_target_enable_exception_callback (arg)
> PTR arg;
>
> to
>
> static int
> cover_target_enable_exception_callback (__builtin_va_list arg)
>
> I consider this to be a more serious problem than the other complaints
> you have.
I think the setup issue is important too. (I don't know if it's more
serious though.) As I mentioned in my first point (which is no longer
quoted), you have to do a configure in the source directory above gdb
in order to to properly run protoize or else it complains that it
can't find certain header files. Also, you need to make sure that the
bfd header files are generated before you start. None of these
problems are insurmountable, but to do things safely with protoize,
and in order to avoid polluting your sources with files that belong in
a build tree, it would be necessary for a script using protoize to
make a complete copy of the source tree somewhere else in order to do
the work.
> 4) ``protoize'' does not reformat long argument lists. The lists
> end up entirely contained on one line.
>
> So... adopt the same solution for it that you chose to adopt for your
> script -- run indent on the output!
Granted. A suitably imaginative script could identify just the lines
that protoize touched and reformat those. I don't think we want to
run indent on entire files however, at least not for this activity.
> For more information on protoize, see the "Running protoize" page:
>
> http://gcc.gnu.org/onlinedocs/gcc_2.html#SEC48
>
> and the "Caveats of using protoize" page:
>
> http://gcc.gnu.org/onlinedocs/gcc_7.html#SEC135
>
> I've used protoize before with good results. It was a fairly
> substantial project, though not as big as gdb.
Okay. Out of curiousity, did the project in question have a large
number of active developers? (This doesn't necessarily matter, but
I think it's probably easier to manage this kind of thing when only
a handful of developers are affected.)
> Two of my goals in creating the scripts for the PARAMS purging
> activities was that the scripts should be 1) easy to invoke and 2)
> require no hand editing of the output when done. I.e, you shouldn't
> have to edit any of the files that these scripts touch in order to fix
>
> I trust that "3)" is:
>
> "be conservative; not convert something if it can't be sure
> of getting it right".
You're right. I should have mentioned this.
> I'd much rather hand convert more of the code than have it make a
> subtle but incorrect change.
I agree completely.
[...]
> Finally, I should note that I've done a test build on GNU/Linux/x86
> and had no build problems, nor did I see any regressions when I ran
> the testsuite.
>
> The fix-decls script is below. I'd be interested in finding out if
> anyone else has a favorite script for doing this sort of thing. Other
> comments welcome too.
>
> I'd be tempted to do a build before running your script; stash away the
> object files; run the script; do another build; compare the object
> files...
Good idea. I'll have to see what gcc does to compare object files.
(I don't think a simple cmp works for ELF files.)
> I consider the lack of (prototyped) function declarations to be more
> serious "problem" than the use of old style function definitions in
> old code. I'd like to see:
>
> . declarations near the top of every file (i.e., before the first
> function definition) for every static function in the file.
>
> . a declaration in an included header file for every non static
> function definition and for every non static function used.
>
> . changes to the default configuration to "encourage" developers to
> include the above declarations.
I don't disagree, but I think that adding prototypes for everything
should be a separate activity. The question is whether it should
occur before the activity covered by my proposal. And if it should
occur before, once again, we'll need to find a way to help automate
the process because if we attempt to do it incrementally by hand
over a period of time, it is likely that it'll never get done.
Kevin
From taylor@cygnus.com Fri Jun 02 13:11:00 2000
From: David Taylor <taylor@cygnus.com>
To: Kevin Buettner <kevinb@cygnus.com>
Cc: gdb@sourceware.cygnus.com
Subject: Re: Proposal: convert function definitions to prototyped form
Date: Fri, 02 Jun 2000 13:11:00 -0000
Message-id: <200006022010.QAA25997@texas.cygnus.com>
X-SW-Source: 2000-06/msg00022.html
Content-length: 4318
Date: Fri, 2 Jun 2000 12:10:42 -0700
From: Kevin Buettner <kevinb@cygnus.com>
On Jun 2, 11:39am, David Taylor wrote:
> 3) ``protoize'' screws up on PTR types. E.g, in breakpoint.c, it
> converted
>
> static int
> cover_target_enable_exception_callback (arg)
> PTR arg;
>
> to
>
> static int
> cover_target_enable_exception_callback (__builtin_va_list arg)
>
> I consider this to be a more serious problem than the other complaints
> you have.
I think the setup issue is important too. (I don't know if it's more
serious though.) As I mentioned in my first point (which is no longer
quoted), you have to do a configure in the source directory above gdb
Sorry, I didn't consider it relevant to what I was replying to.
in order to to properly run protoize or else it complains that it
can't find certain header files. Also, you need to make sure that the
bfd header files are generated before you start. None of these
problems are insurmountable, but to do things safely with protoize,
and in order to avoid polluting your sources with files that belong in
a build tree, it would be necessary for a script using protoize to
make a complete copy of the source tree somewhere else in order to do
the work.
I don't consider the setup issue to be a big issue. It requires some
time, but it doesn't require much human time. Configure in the source
tree, then build. Setup done.
During the commit phase, you don't commit anything that is new -- you
only commit files that existed prior to doing the configure. No
separate tree needed.
> 4) ``protoize'' does not reformat long argument lists. The lists
> end up entirely contained on one line.
>
> So... adopt the same solution for it that you chose to adopt for your
> script -- run indent on the output!
Granted. A suitably imaginative script could identify just the lines
that protoize touched and reformat those. I don't think we want to
run indent on entire files however, at least not for this activity.
Since Stan previously ran indent on all of the files, re-running it
*should* produce no change for stuff that hasn't changed. Should
produce no change. I'm not saying it won't. If it changes its own
output when presented with it as input, I would consider that a bug.
> I've used protoize before with good results. It was a fairly
> substantial project, though not as big as gdb.
Okay. Out of curiousity, did the project in question have a large
number of active developers? (This doesn't necessarily matter, but
I think it's probably easier to manage this kind of thing when only
a handful of developers are affected.)
It was at a former company. There were a small number of active
developers all within the company. The total project was around
200-250K lines of code. There was a great deal less use of #if within
the sources than there is in GDB...
[...]
I don't disagree, but I think that adding prototypes for everything
should be a separate activity. The question is whether it should
occur before the activity covered by my proposal. And if it should
occur before, once again, we'll need to find a way to help automate
the process because if we attempt to do it incrementally by hand
over a period of time, it is likely that it'll never get done.
I agree that it should be a separate activity.
I think that your script is a good thing. And due to the amount of
hand editing that appears to be necessary with protoize vs the amount
that appears to be necessary with your script, I think we should use
your script.
Ultimately, though, since you're doing the work, you get to select the
tool. So long as it is fairly reliable and reasonably quick (quick in
terms of *your time*, not in terms of *elapsed time*), it doesn't
ultimately matter to me what tool you use. (Which is not to say that
I am not interested in knowing what tool you use -- I am interested.)
Like I said, I think your script is a good thing. And I look forward
to you using it to protoize the bulk of the GDB sources.
Kevin
David
From kettenis@wins.uva.nl Fri Jun 02 13:58:00 2000
From: Mark Kettenis <kettenis@wins.uva.nl>
To: gdb@sourceware.cygnus.com
Subject: handling unexpected debugging unformation
Date: Fri, 02 Jun 2000 13:58:00 -0000
Message-id: <200006022058.e52KwS213519@delius.kettenis.local>
X-SW-Source: 2000-06/msg00023.html
Content-length: 1842
Struggling with the misconfigured GCC 2.95.2 used by FreeBSD/Alpha as
its system compiler revealed some weaknesses in GDB with respect to
unexpected debugging information. Some extra stabs present in the
stabs-in-ecoff .mdebug section of an Alpha ELF executable caused GDB
to crash.
The problematic stabs in question are:
* N_BINCL stabs: These cause add_new_header_files to be called, but
since init_header_files() hasn't been called for stabs-in-ecoff,
GDB tries to dereference a null pointer. There are several possible
solutions, and I'll need some help choosing between them :-). Hence
a few questions:
- Should N_BINCL stabs be supported in stabs-in-ecoff?
- Is it acceptable to export free_header_files() and
init_header_files() from dbxread.c?
- Shouldn't mdebugread.c:elfmdebug_build_psymtabs() call
stabsread_new_init() and buildsym_new_init()?
- What about mdebug_build_psymtabs()?
* An extra blank N_SO stab (emitted by GCC for normal stabs-in-ELF):
mdebugread.c:psymtab_to_symtab_1() iterates over all stabs symbols,
calling dbxread.c:process_one_symbol() for them. If
process_one_symbol() sees an N_SO stab it will call end_symtab() if
we've seen an N_SO before, and then calls start_symtab() if the N_SO
stab isn't blank.
After the iteration psymtab_to_symtab_1() also calls end_symtab()
and uses its return value. The problem is that the blank N_SO stab
already finishes creating the symbol table. The end_symtab() in
psymtab_to_symtab_1() tries to do that again, freeing already freed
memory blocks, which again crashed GDB.
(The extra blank N_SO stab in normal ELF objects seems never to be
passed to process_one_symbal()).
Is there a way we can make this a bit more robust? Would setting
subfiles to NULL in buildsymtab.c:end_symtab() be sufficient?
Mark
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2000-06-12 19:48 UTC | newest]
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[not found] <1000602075018.ZM29997@ocotillo.lan>
2000-06-02 5:26 ` Proposal: convert function definitions to prototyped form Mark Kettenis
[not found] ` <1000602151553.ZM30578@ocotillo.lan>
[not found] ` <5mya4om115.fsf@jtc.redback.com>
[not found] ` <3938F700.509FD4AA@cygnus.com>
2000-06-05 11:05 ` J.T. Conklin
[not found] ` <3937816C.E66B9AE0@cygnus.com>
2000-06-03 0:13 ` Kevin Buettner
2000-06-12 18:10 ` Andrew Cagney
2000-06-12 19:48 ` Kevin Buettner
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