Cannot get any flamegraph out of perf run. Is function pointer not enough?

Question

I am running perf on a Google Benchmark. It is compiled with GCC 10 RelWithDebInfo. I am using CentOS on x86.

Option --call-graph fp is the only option that works. Not sure why I cannot go dwarf.

Afterward I run the script from: https://github.com/brendangregg/FlameGraph To get the flamegraph:

perf script | ~/FlameGraph/stackcollapse-perf.pl | ~/FlameGraph/flamegraph.pl > flamegraph.svg

This unfortunately says:

ERROR: No stack counts found

And no flamegraph is produced. However, perf report shows percentages and callstack, even if function names are not always there making it hard to interpret.