drmemory
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DynamoRIO
DynamoRIO
CRASH at 0x..96c1 on appveyor in various tests
I can't reproduce these crashes locally on a win8.1 or other machine.
Appveyor 64-bit has crashed in registers.exe, malloc.exe, and pcache.exe. The crashes always have the address 0x..96c1. Here is an example:
[00:06:17] 8/114 Test #7: registers .........................***Failed 1.83 sec
[00:06:17] STDOUT:
[00:06:17] STDERR: <Starting application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registers.exe (864)>
[00:06:17] <Initial options = -no_dynamic_options -logdir 'C:\projects\drmemory\build\build_drmemory-dbg-64\logs\dynamorio' -client_lib 'C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll;0;`-callstack_style` `0x27` -no_results_to_stderr -logdir `C:\projects\drmemory\build\build_drmemory-dbg-64\logs` -symcache_dir `C:\projects\drmemory\build\build_drmemory-dbg-64\logs\symcache` -lib_blacklist `C:\windows*.d??,C:\Program Files\Common Files\Microsoft Shared*.d??,C:\Program Files (x86)\Common Files\Microsoft Shared*.d??` -resfile 864 ' -code_api -probe_api -msgbox_mask 0 -dumpcore_mask 0x87fd -stack_size 56K -disable_traces -no_enable_traces -max_elide_jmp 0 -max_elide_call 0 -no_shared_traces -bb_ibl_targets -bb_single_restore_prefix -no_shared_trace_ibl_routine -no_enable_reset -no_reset_at_switch_to_os_at_vmm_limit -reset_at_vmm_percent_free_limit 0 -no_reset_at_vmm_full -reset_at_commit_free_limit 0K -reset_every_nth_pending 0 -no_vm_base_near_app -no_inline_ignored_syscalls -native_exec_default_list '' -no_native_exec_managed_code -no_indcall2direct -pad_jmps_mark_no_trace >
[00:06:17] ~~Dr.M~~ Dr. Memory version 1.11.17967
[00:06:17] ~~Dr.M~~ Running "C:/projects/drmemory/build/build_drmemory-dbg-64/tests/registers.exe"
[00:06:17] <Core dump file for application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registers.exe (864) created at C:\projects\drmemory\build\build_drmemory-dbg-64\logs\dynamorio\registers.exe.864.00000000.ldmp>
[00:06:17] <Application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registers.exe (864). Dr. Memory internal crash at PC 0x00000000000996c1. Please report this at http://drmemory.org/issues. Program aborted.
[00:06:17] 0xc0000005 0x00000000 0x00000000000996c1 0x00000000000996c1 0x0000000000000000 0x000004007c250000
[00:06:17] Base: 0x0000000015000000
[00:06:17] Registers: eax=0x0000000000000000 ebx=0x0000000000000000 ecx=0x000004007c250000 edx=0x0000000000000000
[00:06:17] esi=0x00000001f04ce590 edi=0x00000001f04cb3a0 esp=0x00000001f04cb300 ebp=0x0000000000000000
[00:06:17] r8 =0x0000000000000f84 r9 =0x00000001f04cb3f8 r10=0x0000000000000000 r11=0x0000000000000246
[00:06:17] r12=0x0000000000000000 r13=0x0000000000000000 r14=0x0000000000000000 r15=0x0000000000000000
[00:06:17] eflags=0xcccccccc00010246
[00:06:17] 1.11.17967-1-(Mar 12 2019 05:09:04) WinVer=63;Rel=;Build=9600;Edition=ServerDatacenter
[00:06:23] -no_dynamic_options -logdir 'C:\projects\drmemory\build\build_drmemory-dbg-64\logs\dynamorio' -client_lib 'C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll;0;`-callstack_style` `0x27` -no_results_to_stderr -logdir `C:\projects\drmemory\build\build_drmemory-dbg-64\logs` -symcache_dir `C:\projec
[00:06:23] C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll=0x0000000000010000
[00:06:23] C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug/dbghelp.dll=0x0000000000870000
[00:06:23] C:\windows/system32/msvcrt.dll=0x00007ffc840b0000
[00:06:23] C:\windows/system32/kernel32.dll=0x00000001f06d0000
[00:06:23] C:\windows/system32/KERNELBASE.dll=0x00000001f0810000>
I did special runs with verbosity and logs to stderr in PR #2174 and reproduced with -verbose 2 (unfortunately not with higher) in registers.exe. Here is the output from the prior error report to the crash:
#+BEGIN_EXAMPLE
[00:06:18] Error #13: UNINITIALIZED READ: reading 0x000000297263fe10-0x000000297263fe18 8 byte(s)
[00:06:18] # 0 cmpxchg8b_test_asm [C:\projects\drmemory\build\build_drmemory-dbg-64\tests\CMakeFiles\registersB.dir\registers.c_asm.asm.obj.s:1214] (0x0000
7ff6824518a6 <registersB.exe+0x18a6>) modid:3
[00:06:18] # 1 cmpxchg8b_test [c:\projects\drmemory\tests\registers.c:153] (0x00007ff682451346 <registersB.exe+0x1346>) modid:3
[00:06:18] # 2 main [c:\projects\drmemory\tests\registers.c:324] (0x00007ff682451815 <registersB.exe+0x1815>) modid:3
[00:06:18] Note: @0:00:03.828 in thread 748
[00:06:18] Note: instruction: cmpxchg8b (%rcx) %eax %edx %ecx %ebx -> (%rcx) %eax %edx
[00:06:18] error end
[00:06:18] in event_basic_block(tag=0x00007ff682451346)
[00:06:18] set range 0x000000297218fb50-0x000000297218fb58 => 0x0
[00:06:18] replace_free 0x000000297263fe10
[00:06:18] set range 0x000000297263fe10-0x000000297263fe18 => 0x1
[00:06:18] replace_free_common 0x000000297263fe10 == request=8, alloc=16, arena=0x0000002972630000
[00:06:18] set range 0x000000297218fb50-0x000000297218fb58 => 0x1
[00:06:18] in event_basic_block(tag=0x00007ff682451350)
[00:06:18] set range 0x000000297218fb50-0x000000297218fb58 => 0x0
[00:06:18] replace_free 0x000000297263fe40
[00:06:18] set range 0x000000297263fe40-0x000000297263fe48 => 0x1
[00:06:18] replace_free_common 0x000000297263fe40 == request=8, alloc=16, arena=0x0000002972630000
[00:06:18] set range 0x000000297218fb50-0x000000297218fb58 => 0x1
[00:06:18] in event_basic_block(tag=0x00007ff68245135a)
[00:06:18] set range 0x000000297218fb60-0x000000297218fb98 => 0x1
[00:06:18] in event_basic_block(tag=0x00007ff682451815)
[00:06:18] in event_basic_block(tag=0x00007ff682451370)
[00:06:18] set range 0x000000297218fb60-0x000000297218fb98 => 0x3
[00:06:18] set range 0x000000297218fb50-0x000000297218fb58 => 0x0
[00:06:18] replace_malloc (nomatch) 8
[00:06:18] carving out new chunk @0x000000297263fe50 => head=0x000000297263fe50, res=0x000000297263fe70
[00:06:18] replace_alloc_common arena=0x0000002972630000 flags=0x1004 request=8, align=16 alloc=16 => 0x000000297263fe70
[00:06:18] set range 0x000000297263fe70-0x000000297263fe78 => 0x3
[00:06:18] replace_malloc 8 => 0x000000297263fe70
[00:06:18] set range 0x000000297218fb50-0x000000297218fb58 => 0x1
[00:06:18] in event_basic_block(tag=0x00007ff68245137e)
[00:06:18] in event_basic_block(tag=0x00007ff6824518af)
[00:06:18] in event_basic_block(tag=0x00007ff682451394)
[00:06:18] set range 0x000000297218fb50-0x000000297218fb58 => 0x0
[00:06:18] replace_free 0x000000297263fe70
[00:06:18] set range 0x000000297263fe70-0x000000297263fe78 => 0x1
[00:06:18] replace_free_common 0x000000297263fe70 == request=8, alloc=16, arena=0x0000002972630000
[00:06:18] set range 0x000000297218fb50-0x000000297218fb58 => 0x1
[00:06:18] in event_basic_block(tag=0x00007ff68245139e)
[00:06:18] set range 0x000000297218fb60-0x000000297218fb98 => 0x1
[00:06:18] in event_basic_block(tag=0x00007ff68245181a)
[00:06:18] in event_basic_block(tag=0x00007ff6824513b0)
[00:06:18] set range 0x000000297218fb60-0x000000297218fb98 => 0x3
[00:06:18] in event_basic_block(tag=0x00007ff682451a7c)
[00:06:18] in event_basic_block(tag=0x00007ff6824513c7)
[00:06:18] set range 0x000000297218fb60-0x000000297218fb98 => 0x1
[00:06:18] in event_basic_block(tag=0x00007ff68245181f)
[00:06:18] in event_basic_block(tag=0x00007ff682451470)
[00:06:18] set range 0x000000297218fae0-0x000000297218fb98 => 0x3
[00:06:18] set range 0x000000297218fad0-0x000000297218fad8 => 0x0
[00:06:18] replace_malloc (nomatch) 128
[00:06:18] carving out new chunk @0x000000297263fe80 => head=0x000000297263fe80, res=0x000000297263fea0
[00:06:18] replace_alloc_common arena=0x0000002972630000 flags=0x1004 request=128, align=16 alloc=128 => 0x000000297263fea0
[00:06:18] set range 0x000000297263fea0-0x000000297263ff20 => 0x3
[00:06:18] replace_malloc 128 => 0x000000297263fea0
[00:06:18] set range 0x000000297218fad0-0x000000297218fad8 => 0x1
[00:06:18] in event_basic_block(tag=0x00007ff682451481)
[00:06:18] set range 0x000000297218faa0-0x000000297218fac8 => 0x3
[00:06:18] set range 0x000000297218fa70-0x000000297218fa90 => 0x3
<...>
[00:06:18] set range 0x000000297218fa70-0x000000297218fa90 => 0x1
[00:06:18] set range 0x000000297218faa0-0x000000297218fac8 => 0x1
[00:06:18] in event_basic_block(tag=0x00007ff6824514a0)
[00:06:18] in event_basic_block(tag=0x00007ff682451960)
[00:06:18] <Core dump file for application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registersB.exe (2484) created at C:\projects\drmemory\build\build_drmemory-dbg-64\logs\dynamorio\registersB.exe.2484.00000000.ldmp>
[00:06:18] <Application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registersB.exe (2484). Dr. Memory internal crash at PC 0x00000000000996b1. Please report this at http://drmemory.org/issues. Program aborted.
[00:06:18] 0xc0000005 0x00000000 0x00000000000996b1 0x00000000000996b1 0x0000000000000000 0x0000040a5c990000
[00:06:18] Base: 0x0000000015000000
[00:06:18] Registers: eax=0x0000000000000000 ebx=0x0000000000000000 ecx=0x0000040a5c990000 edx=0x0000000000000000
[00:06:18] esi=0x00000029721de590 edi=0x00000029721db3a0 esp=0x00000029721db300 ebp=0x0000000000000000
[00:06:18] r8 =0x0000000000014b93 r9 =0x00000029721db3f8 r10=0x0000000000000000 r11=0x0000000000000246
[00:06:18] r12=0x0000000000000000 r13=0x0000000000000000 r14=0x0000000000000000 r15=0x0000000000000000
[00:06:18] eflags=0xcccccccc00010246
[00:06:18] 1.11.17972-1-(Mar 17 2019 01:26:36) WinVer=63;Rel=;Build=9600;Edition=ServerDatacenter
[00:06:18] -no_dynamic_options -logdir 'C:\projects\drmemory\build\build_drmemory-dbg-64\logs\dynamorio' -client_lib 'C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll;0;`-callstack_style` `0x27` -no_results_to_stderr `-verbose` `2` -logdir `C:\projects\drmemory\build\build_drmemory-dbg-64\logs` -symcache
[00:06:18] C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll=0x0000000000010000
[00:06:18] C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug/dbghelp.dll=0x0000000000870000
[00:06:18] C:\windows/system32/msvcrt.dll=0x00007fff7dbe0000
[00:06:18] C:\windows/system32/kernel32.dll=0x0000002972360000
[00:06:18] C:\windows/system32/KERNELBASE.dll=0x0000002972510000>
[00:06:18] ~~Dr.M~~ WARNING: application exited with abnormal code 0xffffffff
0x00007ff682451346 <registersB.exe+0x1346>) modid:3 => final bb is: 0x00007ff682451960 == registersB.exe+0x1960
Looks like my local build lines up:
0:000> Uf registers!cmpxchg8b_test
registers!cmpxchg8b_test [d:\derek\drmemory\git\src\tests\registers.c @ 150]:
150 00007ff7`619f1310 4883ec38 sub rsp,38h
151 00007ff7`619f1314 b908000000 mov ecx,8
151 00007ff7`619f1319 e8820b0000 call registers!malloc (00007ff7`619f1ea0)
151 00007ff7`619f131e 4889442420 mov qword ptr [rsp+20h],rax
152 00007ff7`619f1323 ba01000000 mov edx,1
152 00007ff7`619f1328 b908000000 mov ecx,8
152 00007ff7`619f132d e8ea0a0000 call registers!calloc (00007ff7`619f1e1c)
152 00007ff7`619f1332 4889442428 mov qword ptr [rsp+28h],rax
153 00007ff7`619f1337 488b542420 mov rdx,qword ptr [rsp+20h]
153 00007ff7`619f133c 488b4c2428 mov rcx,qword ptr [rsp+28h]
153 00007ff7`619f1341 e850050000 call registers!cmpxchg8b_test_asm (00007ff7`619f1896)
154 00007ff7`619f1346 488b4c2420 mov rcx,qword ptr [rsp+20h]
So:
0:000> U registers+14a0
registers!addronly_test+0x30 [d:\derek\drmemory\git\src\tests\registers.c @ 203]:
00007ff7`619f14a0 488b4c2420 mov rcx,qword ptr [rsp+20h]
00007ff7`619f14a5 e8b6040000 call registers!addronly_test_asm (00007ff7`619f1960)
registers!addronly_test_asm [D:\derek\drmemory\git\build_DRtoo_x64_dbg\tests\CMakeFiles\registers.dir\registers.c_asm.asm.obj.s @ 1371]:
1371 00007ff7`619f1960 488bc1 mov rax,rcx
1375 00007ff7`619f1963 53 push rbx
1380 00007ff7`619f1964 fe8080000000 inc byte ptr [rax+80h]
1381 00007ff7`619f196a 48ffc0 inc rax
1382 00007ff7`619f196d 48ffc0 inc rax
1383 00007ff7`619f1970 48ffc0 inc rax
1384 00007ff7`619f1973 48ffc0 inc rax
1385 00007ff7`619f1976 48ffc1 inc rcx
1386 00007ff7`619f1979 48ffc1 inc rcx
1387 00007ff7`619f197c 48ffc1 inc rcx
1388 00007ff7`619f197f 48ffc1 inc rcx
1389 00007ff7`619f1982 eb00 jmp registers!addronly_test_asm+0x24 (00007ff7`619f1984) Branch
registers!addronly_test_asm+0x24 [D:\derek\drmemory\git\build_DRtoo_x64_dbg\tests\CMakeFiles\registers.dir\registers.c_asm.asm.obj.s @ 1392]:
1392 00007ff7`619f1984 fe8080000000 inc byte ptr [rax+80h]
1393 00007ff7`619f198a 48ffc3 inc rbx
Hmm, I don't see how that bb would cause a crash (and it doesn't locally). Stumped.
This has also happened in free.exe: https://ci.appveyor.com/project/DynamoRIO/drmemory/builds/23139994
I think this is the same thing with the shifted address 0x99761. Appveyor suddenly failed on slowesp and noreplace_realloc.
I can't reproduce on my win10-1903 machine.
https://ci.appveyor.com/project/DynamoRIO/drmemory/builds/25514866
[00:11:24] 27/114 Test #26: slowesp ...........................***Failed 4.66 sec
[00:11:24] STDOUT:
[00:11:24] STDERR: <Starting application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registers.exe (1300)>
[00:11:24] <Initial options = -no_dynamic_options -logdir 'C:\projects\drmemory\build\build_drmemory-dbg-64\logs\dynamorio' -client_lib 'C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll;0;`-callstack_style` `0x27` -no_results_to_stderr `-no_esp_fastpath` -logdir `C:\projects\drmemory\build\build_drmemory-dbg-64\logs` -symcache_dir `C:\projects\drmemory\build\build_drmemory-dbg-64\logs\symcache` -lib_blacklist `C:\windows*.d??,C:\Program Files\Common Files\Microsoft Shared*.d??,C:\Program Files (x86)\Common Files\Microsoft Shared*.d??` -resfile 1300 ' -code_api -probe_api -msgbox_mask 0 -dumpcore_mask 0x87fd -stack_size 56K -disable_traces -no_enable_traces -max_elide_jmp 0 -max_elide_call 0 -no_shared_traces -bb_ibl_targets -bb_single_restore_prefix -no_shared_trace_ibl_routine -no_enable_reset -no_reset_at_switch_to_os_at_vmm_limit -reset_at_vmm_percent_free_limit 0 -no_reset_at_vmm_full -reset_at_commit_free_limit 0K -reset_every_nth_pending 0 -vm_size 262144K -no_vm_base_near_app -no_inline_ignored_syscalls -native_exec_default_list '' -no_native_exec_managed_code -no_indcall2direct -pad_jmps_mark_no_trace >
[00:11:24] ~~Dr.M~~ Dr. Memory version 2.1.18072
[00:11:24] ~~Dr.M~~ Running "C:/projects/drmemory/build/build_drmemory-dbg-64/tests/registers.exe"
[00:11:24] <Core dump file for application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registers.exe (1300) created at C:\projects\drmemory\build\build_drmemory-dbg-64\logs\dynamorio\registers.exe.1300.00000000.ldmp>
[00:11:24] <Application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registers.exe (1300). Dr. Memory internal crash at PC 0x0000000000099761. Please report this at http://drmemory.org/issues. Program aborted.
[00:11:24] 0xc0000005 0x00000000 0x0000000000099761 0x0000000000099761 0x0000000000000000 0x0000041155d20000
[00:11:24] Base: 0x0000000015000000
[00:11:24] Registers: eax=0x0000000000000000 ebx=0x0000000000000000 ecx=0x0000041155d20000 edx=0x0000000000000000
[00:11:24] esi=0x000000455707e590 edi=0x000000455707b3a0 esp=0x000000455707b300 ebp=0x0000000000000000
[00:11:24] r8 =0x0000000000022aba r9 =0x000000455707b3f8 r10=0x0000000000000000 r11=0x0000000000000246
[00:11:24] r12=0x0000000000000000 r13=0x0000000000000000 r14=0x0000000000000000 r15=0x0000000000000000
[00:11:24] eflags=0xcccccccc00010246
[00:11:24] 2.1.18072-1-(Jun 25 2019 03:00:11) WinVer=63;Rel=;Build=9600;Edition=ServerDatacenter
[00:11:24] -no_dynamic_options -logdir 'C:\projects\drmemory\build\build_drmemory-dbg-64\logs\dynamorio' -client_lib 'C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll;0;`-callstack_style` `0x27` -no_results_to_stderr `-no_esp_fastpath` -logdir `C:\projects\drmemory\build\build_drmemory-dbg-64\logs` -symc
[00:11:24] C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll=0x0000000000010000
[00:11:24] C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug/dbghelp.dll=0x0000000000870000
[00:11:24] C:\windows/system32/msvcrt.dll=0x00007ffb3f9c0000
[00:11:24] C:\windows/system32/kernel32.dll=0x0000004557210000
[00:11:30] C:\windows/system32/KERNELBASE.dll=0x0000004557350000>
[00:11:30] ~~Dr.M~~ WARNING: application exited with abnormal code 0xffffffff
Continues to happen: https://ci.appveyor.com/project/DynamoRIO/drmemory/builds/27430351
[00:09:09] <Application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registers.exe (2092). Dr. Memory internal crash at PC 0x00000000000998e1. Please report this at http://drmemory.org/issues. Program aborted.
[00:09:09] (2092). Dr. Memory internal crash at PC 0x00000000000998e1. Please
[00:09:55] <Application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\malloc.exe (1340). Dr. Memory internal crash at PC 0x00000000000998e1. Please report this at http://drmemory.org/issues. Program aborted.
[00:10:05] Dr. Memory internal crash at PC 0x00000000000998e1. Please report this at
[00:10:05] <Application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registers.exe (2692). Dr. Memory internal crash at PC 0x00000000000998e1. Please report this at http://drmemory.org/issues. Program aborted.
[00:10:12] (2692). Dr. Memory internal crash at PC 0x00000000000998e1. Please
Seeing a different address in the upper bits after table truncation was fixed? https://ci.appveyor.com/project/DynamoRIO/drmemory/builds/27454088
193<Application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\malloc.exe (2220). Dr. Memory internal crash at PC 0x00007ff6dbb798e1. Please report this at http://drmemory.org/issues. Program aborted.
Again: https://ci.appveyor.com/project/DynamoRIO/drmemory/builds/28889354
[00:10:43] <Application C:\projects\drmemory\build\build_drmemory-dbg-64\tests\registers.exe (2228). Dr. Memory internal crash at PC 0x00007ff7642c98e1. Please report this at http://drmemory.org/issues. Program aborted.
[00:10:43] 0xc0000005 0x00000000 0x00007ff7642c98e1 0x00007ff7642c98e1 0x0000000000000000 0x0000041f33d20000
[00:10:43] Base: 0x0000000015000000
[00:10:43] Registers: eax=0x0000000000000000 ebx=0x0000000000000000 ecx=0x0000041f33d20000 edx=0x0000000000000000
[00:10:43] esi=0x0000007c4f33dbf0 edi=0x0000007c4f33ae70 esp=0x0000007c4f33add0 ebp=0x0000000000000000
[00:10:43] r8 =0x000000000003e67a r9 =0x0000007c4f33aec8 r10=0x0000000000000000 r11=0x0000000000000246
[00:10:44] r12=0x0000000000000000 r13=0x0000000000000000 r14=0x0000000000000000 r15=0x0000000000000000
[00:10:44] eflags=0x0000007c00010246
[00:10:44] 2.2.18215-1-(Nov 15 2019 15:47:43) WinVer=63;Rel=;Build=9600;Edition=ServerDatacenter
[00:10:44] -no_dynamic_options -logdir 'C:\projects\drmemory\build\build_drmemory-dbg-64\logs\dynamorio' -client_lib 'C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll;0;`-callstack_style` `0x27` -no_results_to_stderr `-no_check_uninitialized` -logdir `C:\projects\drmemory\build\build_drmemory-dbg-64\logs
[00:10:44] C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug\drmemorylib.dll=0x00007ff764240000
[00:10:44] C:\projects\drmemory\build\build_drmemory-dbg-64\bin64\debug/dbghelp.dll=0x00007ff764aa0000
[00:10:44] C:\windows/system32/msvcrt.dll=0x00007ffd9fed0000
[00:10:44] C:\windows/system32/kernel32.dll=0x0000007ccf2b0000
[00:10:44] C:\windows/system32/KERNELBASE.dll=0x0000007c4f080000>
[00:10:44] ~~Dr.M~~ WARNING: application exited with abnormal code 0xffffffff
This is a really nasty bug that is making the CI always red, but given that I could not figure it out via diagnostics on Appveyor, nor repro on various Windows machines, my plan was to upgrade DrM to VS2017 (#2250) and thus Appveyor to a more recent Windows to "solve" the problem (well, hide the problem and focus on more modern Windows: not enough resources to solve problems on old OS we can't repro).