When you run powertop with the '--html' option, it fails to produce powertop.html. The commit that causes this issue is: commit 0b9387287fd0055f29786d17ba61f8a5c6099bea $sudo powertop -html Loaded 0 prior measurements Cannot load from file /var/cache/powertop/saved_parameters.powertop RAPL device for cpu 0 RAPL Using PowerCap Sysfs : Domain Mask d RAPL device for cpu 0 RAPL Using PowerCap Sysfs : Domain Mask d RAPL device for cpu 0 RAPL Using PowerCap Sysfs : Domain Mask d Devfreq not enabled Cannot load from file /var/cache/powertop/saved_parameters.powertop Preparing to take measurements unknown op '{' nswamina@nswamina-desktop:~/powertop/test-powertop/powertop/src$ Further debugging using gdb shows the cause to be a segmentation fault: nswamina@nswamina-desktop:~/powertop/test-powertop/powertop/src$ sudo gdb powertop (gdb) r --html Starting program: /home/nswamina/powertop/test-powertop/powertop/src/powertop --html [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Loaded 0 prior measurements Cannot load from file /var/cache/powertop/saved_parameters.powertop RAPL device for cpu 0 RAPL Using PowerCap Sysfs : Domain Mask d RAPL device for cpu 0 RAPL Using PowerCap Sysfs : Domain Mask d RAPL device for cpu 0 RAPL Using PowerCap Sysfs : Domain Mask d Devfreq not enabled Cannot load from file /var/cache/powertop/saved_parameters.powertop Preparing to take measurements unknown op '{' Program received signal SIGSEGV, Segmentation fault. 0x00007ffff72e3b63 in std::string::swap(std::string&) () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (gdb) backtrace #0 0x00007ffff72e3b63 in std::string::swap(std::string&) () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6 #1 0x0000000000415675 in operator= (__str=<unknown type in /home/nswamina/powertop/test-powertop/powertop/src/powertop, CU 0x72c3a, DIE 0x86efe>, this=0x941998) at /usr/include/c++/4.9/bits/basic_string.h:592 #2 report_display_cpu_cstates () at cpu/cpu.cpp:573 #3 0x000000000040fe92 in one_measurement (seconds=seconds@entry=1, workload=workload@entry=0x0) at main.cpp:232 #4 0x00000000004100e2 in make_report (time=20, workload=workload@entry=0x7fffffffd550 "", iterations=iterations@entry=1, file=file@entry=0x7fffffffc550 "powertop.html") at main.cpp:267 #5 0x0000000000406e0e in main (argc=2, argv=0x7fffffffe678) at main.cpp:476