Internal error during isolate with deltas

I've got a second internal error, this one during the isolate operation:

---- exception type = [BUG] ----------
[source]
#011File cat_delta_signature.cpp line 170 : it seems to be a bug here
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZN6libdar4EbugC1ERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEi+0x13d) [0x7ff612dd911d]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(+0x7de9d) [0x7ff612d17e9d]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZNK6libdar8cat_file14inherited_dumpERKNS_15pile_descriptorEb+0x1dd) [0x7ff612db043d]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZNK6libdar13cat_directory14inherited_dumpERKNS_15pile_descriptorEb+0x9c) [0x7ff612da4f7c]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZNK6libdar13cat_directory14inherited_dumpERKNS_15pile_descriptorEb+0x9c) [0x7ff612da4f7c]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZNK6libdar13cat_directory14inherited_dumpERKNS_15pile_descriptorEb+0x9c) [0x7ff612da4f7c]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZNK6libdar13cat_directory14inherited_dumpERKNS_15pile_descriptorEb+0x9c) [0x7ff612da4f7c]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZNK6libdar13cat_directory14inherited_dumpERKNS_15pile_descriptorEb+0x9c) [0x7ff612da4f7c]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZNK6libdar13cat_directory14inherited_dumpERKNS_15pile_descriptorEb+0x9c) [0x7ff612da4f7c]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZNK6libdar9catalogue4dumpERKNS_15pile_descriptorE+0xc5) [0x7ff612d9eb35]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZN6libdar24macro_tools_close_layersERKSt10shared_ptrINS_16user_interactionEERNS_4pileERKNS_14header_versionERKNS_9catalogueEbNS_11crypto_algoENS_11compressionERKSt6vectorINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESaISL_EESP_b+0x453) [0x7ff612e42cd3]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZN6libdar7archive9i_archive10op_isolateERKNS_4pathERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESC_RKNS_23archive_options_isolateE+0x6fb) [0x7ff612e1dfeb]
#011stack dump : /lib/x86_64-linux-gnu/libdar64.so.6000(_ZN6libdar7archive10op_isolateERKNS_4pathERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESB_RKNS_23archive_options_isolateE+0xaa) [0x7ff612d846da]
#011stack dump : dar(+0x45f9c) [0x56360b3b7f9c]
#011stack dump : dar(+0x4f0d0) [0x56360b3c10d0]
#011stack dump : dar(+0x22b71) [0x56360b394b71]
#011stack dump : /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xea) [0x7ff61288ed0a]
#011stack dump : dar(+0x22cea) [0x56360b394cea]
[most outside call]
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INTERNAL ERROR, PLEASE REPORT THE PREVIOUS OUTPUT TO MAINTAINER