rustc 1.30 beta 12 incremental compilation hangs on win 7

[sinesc]

I'm seeing frequent rustc freezes (0% CPU) with incremental compilation enabled on Windows 7. This happens about every 2nd or 3rd build attempt. Once this happens (and after killing the frozen rustc), any further attempts hang forever as well (i.e. I waited 5 minutes). cargo clean resolves the issue until it happens again a few builds later, setting CARGO_INCREMENTAL=0 appears to completely prevent it.

This might be a duplicate of/related to #54627.

I have attached a debugger to get the traces, but I don't have any symbols for rustc, so this is probably useless:

>	ntdll.dll!NtWaitForKeyedEvent�()
 	ntdll.dll!RtlSleepConditionVariableSRW�()
 	kernel32.dll!SleepConditionVariableSRW�()
 	std-955ac6734338b235.dll!000007fedb3c7fa4()
 	std-955ac6734338b235.dll!000007fedb3a7781()
 	rustc_codegen_llvm-llvm.dll!000007fed71f49d2()
 	rustc_codegen_llvm-llvm.dll!000007fed71c8283()
 	rustc_codegen_llvm-llvm.dll!000007fed718739c()
 	rustc_codegen_llvm-llvm.dll!000007fed71c2720()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc915108()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc9384ac()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc8d8fb3()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc8d4e36()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc987961()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc9e27e0()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc92e728()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc9c7908()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc92c325()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc9c6588()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc92b665()
 	std-955ac6734338b235.dll!000007fedb3da2a2()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc9c37b3()
 	rustc_driver-7ae0c7f4e267e2e6.dll!000007fedc9d5f8e()
 	rustc.exe!000000013f071056()
 	std-955ac6734338b235.dll!000007fedb3a8477()
 	std-955ac6734338b235.dll!000007fedb3da2a2()
 	std-955ac6734338b235.dll!000007fedb3ba4c3()
 	rustc.exe!000000013f07104a()
 	rustc.exe!000000013f071299()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!NtWaitForMultipleObjects�()
 	KernelBase.dll!WaitForMultipleObjectsEx()
 	kernel32.dll!WaitForMultipleObjects�()
 	rustc-cfefa64b59573cce.dll!000007fedbea2476()
 	rustc-cfefa64b59573cce.dll!000007fedbea2768()
 	std-955ac6734338b235.dll!000007fedb3da2a2()
 	rustc-cfefa64b59573cce.dll!000007fedbe9e662()
 	std-955ac6734338b235.dll!000007fedb3d8672()
 	std-955ac6734338b235.dll!000007fedb3b48e9()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!NtWaitForKeyedEvent�()
 	ntdll.dll!RtlSleepConditionVariableSRW�()
 	kernel32.dll!SleepConditionVariableSRW�()
 	std-955ac6734338b235.dll!000007fedb3c7fa4()
 	std-955ac6734338b235.dll!000007fedb3a7781()
 	rustc_codegen_llvm-llvm.dll!000007fed70cfb2a()
 	rustc_codegen_llvm-llvm.dll!000007fed71c78f8()
 	rustc_codegen_llvm-llvm.dll!000007fed70c9384()
 	rustc_codegen_llvm-llvm.dll!000007fed70e3346()
 	std-955ac6734338b235.dll!000007fedb3da2a2()
 	rustc_codegen_llvm-llvm.dll!000007fed70d4e59()
 	std-955ac6734338b235.dll!000007fedb3d8672()
 	std-955ac6734338b235.dll!000007fedb3b48e9()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	rustc_codegen_llvm-llvm.dll!000007fed8af53a0()
 	rustc_codegen_llvm-llvm.dll!000007fed8af564b()
 	rustc_codegen_llvm-llvm.dll!000007fed8af554e()
 	ntdll.dll!RtlProcessFlsData�()
 	ntdll.dll!LdrShutdownThread�()
 	ntdll.dll!RtlExitUserThread�()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrGetProcedureAddressEx�()
 	ntdll.dll!LdrGetProcedureAddress�()
 	KernelBase.dll!GetProcAddress()
 	rustc_codegen_llvm-llvm.dll!000007fed8af6236()
 	rustc_codegen_llvm-llvm.dll!000007fed8af6bdc()
 	rustc_codegen_llvm-llvm.dll!000007fed8af2e9a()
 	rustc_codegen_llvm-llvm.dll!000007fed8ad3d7d()
 	rustc_codegen_llvm-llvm.dll!000007fed73bc2fe()
 	rustc_codegen_llvm-llvm.dll!000007fed73bc203()
 	rustc_codegen_llvm-llvm.dll!000007fed73bb9e1()
 	rustc_codegen_llvm-llvm.dll!000007fed752c6e7()
 	rustc_codegen_llvm-llvm.dll!000007fed7c20cbc()
 	rustc_codegen_llvm-llvm.dll!000007fed7c19b56()
 	rustc_codegen_llvm-llvm.dll!000007fed7c239d3()
 	rustc_codegen_llvm-llvm.dll!000007fed733a810()
 	rustc_codegen_llvm-llvm.dll!000007fed72469f9()
 	rustc_codegen_llvm-llvm.dll!000007fed70f40bf()
 	rustc_codegen_llvm-llvm.dll!000007fed70cd5d2()
 	rustc_codegen_llvm-llvm.dll!000007fed70e3399()
 	std-955ac6734338b235.dll!000007fedb3da2a2()
 	rustc_codegen_llvm-llvm.dll!000007fed70d4b9a()
 	std-955ac6734338b235.dll!000007fedb3d8672()
 	std-955ac6734338b235.dll!000007fedb3b48e9()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrShutdownThread�()
 	ntdll.dll!RtlExitUserThread�()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrShutdownThread�()
 	ntdll.dll!RtlExitUserThread�()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrShutdownThread�()
 	ntdll.dll!RtlExitUserThread�()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrShutdownThread�()
 	ntdll.dll!RtlExitUserThread�()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrpInitializeThread�()
 	ntdll.dll!_LdrpInitialize�()
 	ntdll.dll!LdrInitializeThunk�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrpInitializeThread�()
 	ntdll.dll!_LdrpInitialize�()
 	ntdll.dll!LdrInitializeThunk�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrpInitializeThread�()
 	ntdll.dll!_LdrpInitialize�()
 	ntdll.dll!LdrInitializeThunk�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	rustc_codegen_llvm-llvm.dll!000007fed8af53e0()
 	rustc_codegen_llvm-llvm.dll!000007fed8af5533()
 	rustc_codegen_llvm-llvm.dll!000007fed8af5926()
 	rustc_codegen_llvm-llvm.dll!000007fed8af13c9()
 	rustc_codegen_llvm-llvm.dll!000007fed8ad0bf6()
 	rustc_codegen_llvm-llvm.dll!000007fed8ad0471()
 	rustc_codegen_llvm-llvm.dll!000007fed8ad06a1()
 	ntdll.dll!LdrpInitializeThread�()
 	ntdll.dll!_LdrpInitialize�()
 	ntdll.dll!LdrInitializeThunk�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	rustc_codegen_llvm-llvm.dll!000007fed8af53a0()
 	rustc_codegen_llvm-llvm.dll!000007fed8af564b()
 	rustc_codegen_llvm-llvm.dll!000007fed8af554e()
 	ntdll.dll!RtlProcessFlsData�()
 	ntdll.dll!LdrShutdownThread�()
 	ntdll.dll!RtlExitUserThread�()
 	kernel32.dll!BaseThreadInitThunk�()
 	ntdll.dll!RtlUserThreadStart�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrpInitializeThread�()
 	ntdll.dll!_LdrpInitialize�()
 	ntdll.dll!LdrInitializeThunk�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrpInitializeThread�()
 	ntdll.dll!_LdrpInitialize�()
 	ntdll.dll!LdrInitializeThunk�()

>	ntdll.dll!ZwWaitForSingleObject�()
 	ntdll.dll!RtlpWaitOnCriticalSection�()
 	ntdll.dll!RtlEnterCriticalSection�()
 	ntdll.dll!LdrpInitializeThread�()
 	ntdll.dll!_LdrpInitialize�()
 	ntdll.dll!LdrInitializeThunk�()

I had this issue too, your fix solved the issue. Hope this gets fixed for others.

[pietroalbini]

Was this working fine on Rust 1.29?

[Mark-Simulacrum]

Cc @michaelwoerister

[sinesc]

@pietroalbini I never experienced the issue with 1.29

There is also a post on reddit about the it, in case it might be helpful: https://www.reddit.com/r/rust/comments/9xseoa/rustc_hangs_on_windows_7_anyone_else/

[pietroalbini]

Ok, marking this as a stable-to-stable regression.

[michaelwoerister]

Did anyone ever see this on other platforms too?

[pnkfelix]

triage: Marking as P-high for now, but am not opposed to downgrading to P-medium if others think that more appropriate.

[pnkfelix]

discussed at T-compiler meeting. Based on the End-of-Life schedule for Windows 7, we assume it is not a tier 1 platform for Rust, and therefore we are downgrading this to P-medium.