How to deal with 'fatal: Failed to get proc symbol via libunwind: -2.'

[eddelbuettel]

Once I set -m I seem to end up with the error above. Any idea how to overcome this?

Ubuntu 23.10.

[atheriel]

That code is UNW_ENOMEM. According to unw_get_proc_name(3) this means that the symbol is too long for the buffer provided, so evidently we need to (1) increase the size of that buffer; and (2) handle that as the non-fatal error that it is, as per their docs.

[eddelbuettel]

Very nice. I can try that locally. Can you point to the respective line(s) ?

[atheriel]

It's here:

xrprof/src/xrprof.c

Lines 240 to 251 in 00d4d7a

	if ((ret = unw_get_proc_name(&uw_cursor, sym, sizeof(sym), &offset)) < 0) {
	if (ret == -UNW_EUNSPEC || ret == -UNW_ENOINFO) {
	fprintf(outfile, "\"<Native:0x%lx>\" ", ip);
	continue;
	} else if (ret != -UNW_ENOINFO) {
	code++;
	fprintf(stderr, "fatal: Failed to get proc symbol via libunwind: %d.\n",
	ret);
	goto done;
	}
	/* Symbol is truncated but otherwise fine. */
	}

[eddelbuettel]

So size of sym is what needs to change?

[eddelbuettel]

That worked! Care for a PR? Preferred size. I picked 1024 because why not? and 512 may work too.

[atheriel]

The poor soul who encounters a symbol longer than 1KB. A PR would be great!

[eddelbuettel]

Narrator: Dirk was last heard mumbling something about Pareto-Efficiency ... Can't take Economics out of him it seems.

PR will be forthcoming.