Correct. When I run it with -f, I get "Segmentation fault" right when I connect to a web browser on 127.0.0.1:8000.
That's the only message I get printed on the console.
Valgrind log:
==26190== Memcheck, a memory error detector
==26190== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==26190== Using Valgrind-3.9.0 and LibVEX; rerun with -h for copyright info
==26190== Command: ./mlvfs MLVFS -f --mlv-dir=/path/to/mlvs
==26190==
webgui start
webgui run
webgui poll
webgui poll
webgui poll
webgui poll
webgui poll
webgui poll
webgui poll
==26190== Thread 2:
==26190== Invalid read of size 8
==26190== at 0x409059: xref_sort (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x4098A7: make_index (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x409B0C: build_index (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x409E23: force_index (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x409E79: get_index (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x409F15: mlv_get_frame_count (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x4375D5: webgui_generate_mlv_html (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x437F1E: webgui_generate_html (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x4385A0: webgui_handler (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x42AE5A: call_user (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x42FD78: call_request_handler (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x4309DF: call_request_handler_if_data_is_buffered (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== Address 0x0 is not stack'd, malloc'd or (recently) free'd
==26190==
==26190==
==26190== Process terminating with default action of signal 11 (SIGSEGV)
==26190== Access not within mapped region at address 0x0
==26190== at 0x409059: xref_sort (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x4098A7: make_index (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x409B0C: build_index (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x409E23: force_index (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x409E79: get_index (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x409F15: mlv_get_frame_count (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x4375D5: webgui_generate_mlv_html (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x437F1E: webgui_generate_html (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x4385A0: webgui_handler (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x42AE5A: call_user (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x42FD78: call_request_handler (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== by 0x4309DF: call_request_handler_if_data_is_buffered (in /home/alex/src/ml/mlvfs/mlvfs/mlvfs/mlvfs)
==26190== If you believe this happened as a result of a stack
==26190== overflow in your program's main thread (unlikely but
==26190== possible), you can try to increase the size of the
==26190== main thread stack using the --main-stacksize= flag.
==26190== The main thread stack size used in this run was 8388608.
==26190==
==26190== HEAP SUMMARY:
==26190== in use at exit: 868,724 bytes in 105 blocks
==26190== total heap usage: 1,096 allocs, 991 frees, 1,604,352 bytes allocated
==26190==
==26190== LEAK SUMMARY:
==26190== definitely lost: 917 bytes in 34 blocks
==26190== indirectly lost: 0 bytes in 0 blocks
==26190== possibly lost: 1,088 bytes in 4 blocks
==26190== still reachable: 866,719 bytes in 67 blocks
==26190== suppressed: 0 bytes in 0 blocks
==26190== Rerun with --leak-check=full to see details of leaked memory
==26190==
==26190== For counts of detected and suppressed errors, rerun with: -v
==26190== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 2 from 2)
edit: it was caused by an invalid MLV (created by latest fullres silent code). Deleting that MLV solved the crash.
edit2: fix commited, thanks dmilligan for write access.