now().utc fails with --gc:arc

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on latest devel , linux

compile with : nim c --gc:arc -r test350
    
    
    #test350.nim
    
    import times
    echo now().utc
    
    
    
    Run

output
    
    
    
    /home/lxuser/.choosenim/toolchains/nim-#devel/lib/pure/times.nim(1090) 
test350
    /home/lxuser/.choosenim/toolchains/nim-#devel/lib/system/refs_v2.nim(162) 
nimRawDispose
    /home/lxuser/.choosenim/toolchains/nim-#devel/lib/system/alloc.nim(972) 
dealloc
    /home/lxuser/.choosenim/toolchains/nim-#devel/lib/system/alloc.nim(871) 
rawDealloc
    /home/lxuser/.choosenim/toolchains/nim-#devel/lib/system/avltree.nim(74) del
    SIGSEGV: Illegal storage access. (Attempt to read from nil?)
    
    
    
    Run

compile with : nim c --gc:orc -r test350

output
    
    
    2020-07-11T21:26:38Z
    
    
    
    Run