On Sun, Jan 04, 2004 at 06:56:05PM +0100, Christoph Jaeschke wrote:
Hi,
I would like to propose a offset based member name lookup of
structs/classes. Assume:
struct X {
int a;
int b;
};
struct Y {
struct X x[4];
int c;
};
struct Z {
Y y;
};
If you apply a patch for gdb 6.0 I've prepared, you can ask gdb by
ptype Z + 28
about Z's relative name at offset 28
.y.x[3].b
using
ptype Z+28, typechain
gdb will append also the typechain
.y.x[3].b, typechain = ::Y::X[4]::int
There may be a better suited command than 'ptype' for it, it was choosen
just because it was the simplest way to add it.
The patch contains also a caching mechanism, speeding up a lot if you do
many lookups in big nested structures. It has a minimal memory
requirement and will not hurt for single lookups.
The patch can be send if you are interested in.
Well, I don't like the syntax, but I think this is a wonderful idea.
The other feature I've been meaning to add since forever is a variant
of ptype which shows byte offsets for every field.
The problem with using ptype is that "Z+28" already has a meaning; gdb
will try to add the two, or call an overloaded + operator in C++, et
cetera. This should probably be a new command; that'll be more useful
for MI anyway.