Exception in cache.cpp

While performing a full backup last night I suddenly got this exception:

Final memory cleanup...
---- exception type = [BUG] ----------
[source]
	File cache.cpp line 562 : it seems to be a bug here
	stack dump : /usr/lib64/libdar64.so.6000(_ZN6libdar4EbugC2ERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEi+0x13d) [0x7f0230765fdd]
	stack dump : /usr/lib64/libdar64.so.6000(+0x7b896) [0x7f023069b896]
	stack dump : /usr/lib64/libdar64.so.6000(_ZN6libdar6escape18inherited_truncateERKNS_8limitintImEE+0x47) [0x7f023076d8b7]
	stack dump : /usr/lib64/libdar64.so.6000(+0x16d783) [0x7f023078d783]
	stack dump : /usr/lib64/libdar64.so.6000(_ZN6libdar17filtre_sauvegardeERKSt10shared_ptrINS_16user_interactionEERKNS_4maskES7_RKNS_15pile_descriptorERNS_9catalogueERKSB_RKNS_4pathEbbbbbRNS_10statisticsEbS7_S7_RKNS_8limitintImEEbSN_bbRKNS_14filesystem_idsENS_17comparison_fieldsEbbbSN_SN_SN_SN_RKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES7_bRKSt3setINS_10fsa_familyESt4lessIS11_ESaIS11_EESZ_bSN_S7_bbRKS10_ISX_S12_ISX_ESaISX_EENS_23modified_data_detectionERKNS_20delta_sig_block_sizeE+0xbff) [0x7f0230797c1f]
	stack dump : /usr/lib64/libdar64.so.6000(_ZN6libdar7archive9i_archive16op_create_in_subENS1_9operationERKNS_4pathERKSt10shared_ptrINS_8entrepotEEPNS_9catalogueEPKSB_bRKNS_4maskESH_RKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESP_bRKNS_11crit_actionEbbbbbbRKNS_8limitintImEEbNS_11compressionEmmSW_SW_SH_SP_NS_11crypto_algoERKNS_11secu_stringEjRKSt6vectorISN_SaISN_EES16_SH_SW_bSP_SW_bbbRKNS_14filesystem_idsENS_17comparison_fieldsEbbbSW_SP_SW_SW_bbbSW_SP_NS_9hash_algoESW_SP_SH_bRKSt3setINS_10fsa_familyESt4lessIS1D_ESaIS1D_EEmmbbSH_SW_bbRKS1C_ISN_S1E_ISN_ES13_ENS_23modified_data_detectionESW_S1B_RKNS_20delta_sig_block_sizeEPNS_10statisticsE+0xdd4) [0x7f02307aecb4]
	stack dump : /usr/lib64/libdar64.so.6000(_ZN6libdar7archive9i_archive12op_create_inENS1_9operationERKNS_4pathERKSt10shared_ptrINS_8entrepotEEPS0_RKNS_4maskESE_RKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESM_bbbbbbbRKNS_8limitintImEEbNS_11compressionEmmSQ_SQ_SE_SM_NS_11crypto_algoERKNS_11secu_stringEjRKSt6vectorISK_SaISK_EES10_SE_SQ_bSM_SQ_bbbRKNS_14filesystem_idsENS_17comparison_fieldsEbbSQ_SM_SQ_SQ_bbSQ_SM_NS_9hash_algoESQ_SM_SE_bRKSt3setINS_10fsa_familyESt4lessIS17_ESaIS17_EEmmbbSE_SQ_bbRKS16_ISK_S18_ISK_ESX_ENS_23modified_data_detectionESQ_S15_RKNS_20delta_sig_block_sizeEPNS_10statisticsE+0xb0a) [0x7f02307b290a]
	stack dump : /usr/lib64/libdar64.so.6000(_ZN6libdar7archive9i_archiveC1ERKSt10shared_ptrINS_16user_interactionEERKNS_4pathES9_RKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESH_RKNS_22archive_options_createEPNS_10statisticsE+0xbf9) [0x7f02307b3cf9]
	stack dump : /usr/lib64/libdar64.so.6000(_ZN6libdar7archiveC2ERKSt10shared_ptrINS_16user_interactionEERKNS_4pathES8_RKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESG_RKNS_22archive_options_createEPNS_10statisticsE+0x11f) [0x7f0230711fdf]
	stack dump : dar(+0x49dff) [0x55b85e629dff]
	stack dump : dar(+0x4ef48) [0x55b85e62ef48]
	stack dump : dar(+0x22681) [0x55b85e602681]
	stack dump : /lib64/libc.so.6(+0x292fa) [0x7f022fd6c2fa]
	stack dump : /lib64/libc.so.6(__libc_start_main+0x78) [0x7f022fd6c3a8]
	stack dump : dar(+0x227fa) [0x55b85e6027fa]
[most outside call]
-----------------------------------

INTERNAL ERROR, PLEASE REPORT THE PREVIOUS OUTPUT TO MAINTAINER

It is quite hard, repeating the run produced exactly the same result.I
have a completely current Gentoo system; dar is version 2.7.2 and was
updated on 08-10-2021; glibc is 2.34-r4.

Any ideas?

Thanks
Robin
-- 
----------------------------------------------------------------------
Robin Atwood.

"Ship me somewheres east of Suez, where the best is like the worst,
 Where there ain't no Ten Commandments an' a man can raise a thirst"
         from "Mandalay" by Rudyard Kipling
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