Encounter duplicate symbol errors:

65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in Accessible2_3_p.obj
65:01.18 lld-link: error: duplicate symbol: UserMarshalRoutines in Accessible2_2_p.obj and in Accessible2_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in Accessible2_p.obj
65:01.18 lld-link: error: duplicate symbol: UserMarshalRoutines in Accessible2_2_p.obj and in AccessibleAction_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleAction_p.obj
65:01.18 lld-link: error: duplicate symbol: UserMarshalRoutines in Accessible2_2_p.obj and in AccessibleApplication_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleApplication_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleComponent_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleDocument_p.obj

_p.obj and in AccessibleEditableText_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleEditableText_p.obj
65:01.18 lld-link: error: duplicate symbol: UserMarshalRoutines in Accessible2_2_p.obj and in AccessibleHyperlink_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleHyperlink_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleHypertext2_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleHypertext_p.obj
65:01.18 lld-link: error: duplicate symbol: UserMarshalRoutines in Accessible2_2_p.obj and in AccessibleImage_p.obj
65:01.18 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleImage_p.obj
65:01.20 lld-link: error: duplicate symbol: UserMarshalRoutines in Accessible2_2_p.obj and in AccessibleRelation_p.obj
65:01.20 lld-link: error: duplicate symbol: Object_StubDesc in Accessible2_2_p.obj and in AccessibleRelation_p.obj
65:01.20 lld-link: error: duplicate symbol: UserMarshalRoutines in Accessible2_2_p.obj and in AccessibleTable2_p.obj
65:01.20 lld-link: error: too many errors emitted, stopping now (use /errorlimit:0 to see all errors)
65:01.21 accessible/ipc/win/handler/module.res

rust toolchain stable-x86_64-pc-windows-msvc (default)
LLVM 9.0
window 10 1803
VS 2019

Execute mach bootstrap fail in enterprise internal network. Cannot access the stable-x86_64-pc-windows-msvc. The file and server is not accessable https://firefoxci.taskcluster-artifacts.net/AoaDar5MSnCR99F7hSIsDA/0/public/chain-of-trust.json

https://firefoxci.taskcluster-artifacts.net/AoaDar5MSnCR99F7hSIsDA/0/public/chain-of-trust.json {"socket5": "web-proxy.sg.softwaregrp.net:8080", "http": "web-proxy.sg.softwaregrp.net:8080", "https": "web-proxy.sg.softwaregrp.net:8080"}
Error running mach:

['artifact', 'toolchain', '--from-build', 'win64-node']

The error occurred in code that was called by the mach command. This is either
a bug in the called code itself or in the way that mach is calling it.
You can invoke |./mach busted| to check if this issue is already on file. If it
isn't, please use |./mach busted file| to report it. If |./mach busted| is
misbehaving, you can also inspect the dependencies of bug 1543241.

If filing a bug, please include the full output of mach, including this error
message.

The details of the failure are as follows:

ConnectionError: HTTPSConnectionPool(host='firefoxci.taskcluster-artifacts.net', port=443): Max retries exceeded with url: /AoaDar5MSnCR99F7hSIsDA/0/public/chain-of-trust.json (Caused by ProxyError('Cannot connect to proxy.', error('Tunnel
connection failed: 302 Found',)))