cmd/gc: potentially invalid DWARF in Go binaries

[alberts]

What does 'go version' print?

tip

What steps reproduce the problem?

git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
cd linux/tools/perf
make
go test -c net/http

this works:

/path/to/perf probe -x /path/to/perf --line show_line_range

this segfaults the perf tool:

/path/to/perf probe -x /path/to/http.test --line findrunnable

this usually happened due to bad DWARF info.

What should have happened instead?

print source code of function.

Please provide any additional information below.

GDB backtrace here:

https://groups.google.com/d/msg/golang-dev/N9BHbxZtMRc/SPtt4pmdZqoJ

[ianlancetaylor]

Comment 1:

It would be nice if somebody investigated this further, but it's pretty hard to know
what to change based on this report.  I checked the GNU binutils readelf program and it
has no evident problem parsing the line number information in http.test.

Labels changed: added release-none, repo-main.

[alberts]

Comment 2:

I'll try to step through perf's logic to see where things are going wrong and report
back.

[rsc]

Comment 3:

Status changed to TimedOut.