cmake suddenly stopped working

cmake suddenly stopped working

[Norton Allen]

Windows 10

Cygwin installed all up to date

cmake 3.17.3-2, which does not appear to have changed since August

Symptoms: cmake fails silently with (or without) any arguments, 
including --help. Exit code is 127

I tried to reinstall cmake, the file appears to be identical

cygcheck -s and cygcheck /usr/bin/cmake both look OK to to me, though 
I'd be happy to upload if anyone is interested.

My AV is ESET. Tried disabling it to no effect.

This could have been caused by a recent cygwin update. The following 
were all installed last Friday. Would anyone like to guess which are 
worth checking? I will cross-check with the cygcheck output for cmake.

Is anyone else seeing this? Any suggestions?

    Nov 13 11:30 gdb.lst.gz
    Nov 13 11:30 git.lst.gz
    Nov 13 11:30 gcc-g++.lst.gz
    Nov 13 11:30 libsource-highlight4.lst.gz
    Nov 13 11:30 openssh.lst.gz
    Nov 13 11:29 gcc-core.lst.gz
    Nov 13 11:29 libboost_regex1.66.lst.gz
    Nov 13 11:29 make.lst.gz
    Nov 13 11:29 libfido2.lst.gz
    Nov 13 11:29 libsource-highlight-common.lst.gz
    Nov 13 11:29 libzstd1.lst.gz
    Nov 13 11:29 libisl22.lst.gz
    Nov 13 11:29 libicu61.lst.gz
    Nov 13 11:29 libguile2.2_1.lst.gz
    Nov 13 11:29 libcbor.lst.gz
    Nov 13 11:29 libjsoncpp24.lst.gz
    Nov 13 11:29 screen.lst.gz
    Nov 13 11:29 libncurses-devel.lst.gz
    Nov 13 11:29 less.lst.gz
    Nov 13 11:29 graphviz.lst.gz
    Nov 13 11:29 file.lst.gz
    Nov 13 11:29 doxygen.lst.gz
    Nov 13 11:29 cygwin-doc.lst.gz
    Nov 13 11:29 bzip2.lst.gz

Re: cmake suddenly stopped working

[Mark Geisert]

Norton Allen wrote:
> Windows 10
> 
> Cygwin installed all up to date
> 
> cmake 3.17.3-2, which does not appear to have changed since August
> 
> Symptoms: cmake fails silently with (or without) any arguments, including --help. 
> Exit code is 127

That exit code usually indicates a missing library at runtime.

> I tried to reinstall cmake, the file appears to be identical
> 
> cygcheck -s and cygcheck /usr/bin/cmake both look OK to to me, though I'd be happy 
> to upload if anyone is interested.
> 
> My AV is ESET. Tried disabling it to no effect.
> 
> This could have been caused by a recent cygwin update. The following were all 
> installed last Friday. Would anyone like to guess which are worth checking? I will 
> cross-check with the cygcheck output for cmake.
> 
> Is anyone else seeing this? Any suggestions?

I'm not seeing it.  'cmake --help' works for me.
Does 'ldd /usr/bin/cmake' give any hint?

..mark

Re: cmake suddenly stopped working

[Norton Allen]

On 11/17/2020 5:48 PM, Mark Geisert wrote:
> Norton Allen wrote:
>> Is anyone else seeing this? Any suggestions?
>
> I'm not seeing it.  'cmake --help' works for me.
> Does 'ldd /usr/bin/cmake' give any hint? 

ldd did not complain, but your question reminded me that I should try 
running under strace. That produce the complaint:

    The procedure entry point
    _ZNSt19basic_ostringstreamlcSt11char_traitslcESalcEEC1Ev could not
    be located in the dynamic link library C:\cygwin64\bin\cmake.exe

(I had to type that in, as I could not copy from strace's error dialog.)

That looks like it might be an issue with the g++ library? Any chance 
there was a change in the library that might require a recompile/relink?

I will try rolling that one back.

Re: cmake suddenly stopped working

[Norton Allen]

On 11/17/2020 6:21 PM, Norton Allen wrote:
> On 11/17/2020 5:48 PM, Mark Geisert wrote:
>> Norton Allen wrote:
>>> Is anyone else seeing this? Any suggestions?
>>
>> I'm not seeing it.  'cmake --help' works for me.
>> Does 'ldd /usr/bin/cmake' give any hint? 
>
> ldd did not complain, but your question reminded me that I should try 
> running under strace. That produce the complaint:
>
>    The procedure entry point
>    _ZNSt19basic_ostringstreamlcSt11char_traitslcESalcEEC1Ev could not
>    be located in the dynamic link library C:\cygwin64\bin\cmake.exe
>
> (I had to type that in, as I could not copy from strace's error dialog.)
>
> That looks like it might be an issue with the g++ library? Any chance 
> there was a change in the library that might require a recompile/relink?
>
> I will try rolling that one back. 


Rolling back to gcc-g++ 9.3.0 did not help.

I did find that entry point string in cmake.exe (all the lowercase 'L's 
I typed in that are actually capital i's. My font makes no distinction) 
and I was able to locate a matching string in 
/lib/gcc/x86_64-pc-cygwin/9.3.0/libstdc++.a, but not in libstdc++.dll.a. 
Running strings on the /usr/bin/cygstdc++-6.dll showed the same 
information. Maybe I need to roll back further!

Re: cmake suddenly stopped working

[Norton Allen]

On 11/17/2020 6:48 PM, Norton Allen wrote:
> On 11/17/2020 6:21 PM, Norton Allen wrote:
>> On 11/17/2020 5:48 PM, Mark Geisert wrote:
>>> Norton Allen wrote:
>>>> Is anyone else seeing this? Any suggestions?
>>>
>>> I'm not seeing it.  'cmake --help' works for me.
>>> Does 'ldd /usr/bin/cmake' give any hint? 
>>
>> ldd did not complain, but your question reminded me that I should try 
>> running under strace. That produce the complaint:
>>
>>    The procedure entry point
>>    _ZNSt19basic_ostringstreamlcSt11char_traitslcESalcEEC1Ev could not
>>    be located in the dynamic link library C:\cygwin64\bin\cmake.exe
>>
>> (I had to type that in, as I could not copy from strace's error dialog.)
>>
>> That looks like it might be an issue with the g++ library? Any chance 
>> there was a change in the library that might require a recompile/relink?
>>
>> I will try rolling that one back. 
>
>
> Rolling back to gcc-g++ 9.3.0 did not help.
>
> I did find that entry point string in cmake.exe (all the lowercase 
> 'L's I typed in that are actually capital i's. My font makes no 
> distinction) and I was able to locate a matching string in 
> /lib/gcc/x86_64-pc-cygwin/9.3.0/libstdc++.a, but not in 
> libstdc++.dll.a. Running strings on the /usr/bin/cygstdc++-6.dll 
> showed the same information. Maybe I need to roll back further!
>
This seems to be the crux of it. That entry point is simply not in the 
g++ shared library. I have not figured out why this cropped up today, 
since it is not present in the current (10.2.0-1) or previous (9.3.0-2) 
versions. I will trying going back to 7.4.0.1, but it's hard to imagine 
it's been gone so long and I haven't seen the problem before today.

     nort@easwhlpt3425080 /usr/bin
     $ strings cygstdc++-6.dll | grep 
_ZNSt19basic_ostringstreamIcSt11char_traits
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEE3strERKSs
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEE4swapERS3_
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1EOS3_
_ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1ERKSsSt13_Ios_Openmode
_ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1ESt13_Ios_Openmode
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC2EOS3_
_ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC2ERKSsSt13_Ios_Openmode
_ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC2ESt13_Ios_Openmode
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEED0Ev
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEED1Ev
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEED2Ev
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEaSEOS3_

     nort@easwhlpt3425080 /usr/bin
     $ strings cmake.exe | grep _ZNSt19basic_ostringstreamIcSt11char_traits
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev
     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEED1Ev

Does this seem like a problem that is likely to be resolved by 
rebuilding cmake?

Re: cmake suddenly stopped working

[Norton Allen]

Rolling back cmake from 3.17.3-2 to 3.14.5-1 seems to have resolved the 
problem.

Any idea why no one else seems to be seeing this problem with 3.17.3-2?

Re: cmake suddenly stopped working

[Lemures Lemniscati]

On Tue, 17 Nov 2020 19:24:12 -0500, Norton Allen
> Rolling back cmake from 3.17.3-2 to 3.14.5-1 seems to have resolved the problem.
> 
> Any idea why no one else seems to be seeing this problem with 3.17.3-2?
> 

If it is caused by incomplete rebasing, a full rebase might make it work.

cf. https://www.cygwin.com/faq.html#faq.using.fixing-fork-failures
|| Force a full rebase: Run rebase-trigger fullrebase, exit all Cygwin programs and run Cygwin setup.

Lem

Re: cmake suddenly stopped working

[Norton Allen]

On 11/18/2020 5:40 AM, Lemures Lemniscati via Cygwin wrote:
> On Tue, 17 Nov 2020 19:24:12 -0500, Norton Allen
>> Rolling back cmake from 3.17.3-2 to 3.14.5-1 seems to have resolved the problem.
>>
>> Any idea why no one else seems to be seeing this problem with 3.17.3-2?
>>
> If it is caused by incomplete rebasing, a full rebase might make it work.
>
> cf. https://www.cygwin.com/faq.html#faq.using.fixing-fork-failures
> || Force a full rebase: Run rebase-trigger fullrebase, exit all Cygwin programs and run Cygwin setup.
Thanks Lem. I gave this a try, but no luck. That does not seem to be my 
problem.

Re: cmake suddenly stopped working

[Marco Atzeri]

On 18.11.2020 01:24, Norton Allen wrote:
> Rolling back cmake from 3.17.3-2 to 3.14.5-1 seems to have resolved the 
> problem.
> 
> Any idea why no one else seems to be seeing this problem with 3.17.3-2?
> 

I assume you had an incomplete upgrade.

what is the output of "cygcheck cmake" ?

  $ cygcheck cmake
Found: D:\cygwin64\bin\cmake.exe
D:\cygwin64\bin\cmake.exe
   D:\cygwin64\bin\cygwin1.dll
     C:\WINDOWS\system32\KERNEL32.dll
       C:\WINDOWS\system32\ntdll.dll
       C:\WINDOWS\system32\KERNELBASE.dll
   D:\cygwin64\bin\cyggcc_s-seh-1.dll
   D:\cygwin64\bin\cygstdc++-6.dll
   D:\cygwin64\bin\cygarchive-13.dll
     D:\cygwin64\bin\cygbz2-1.dll
     D:\cygwin64\bin\cygcrypto-1.1.dll
       D:\cygwin64\bin\cygz.dll
     D:\cygwin64\bin\cygiconv-2.dll
     D:\cygwin64\bin\cyglz4-1.dll
     D:\cygwin64\bin\cyglzma-5.dll
     D:\cygwin64\bin\cyglzo2-2.dll
     D:\cygwin64\bin\cygxml2-2.dll
     D:\cygwin64\bin\cygzstd-1.dll
   D:\cygwin64\bin\cygcurl-4.dll
     D:\cygwin64\bin\cygbrotlidec-1.dll
       D:\cygwin64\bin\cygbrotlicommon-1.dll
     D:\cygwin64\bin\cyggssapi_krb5-2.dll
       D:\cygwin64\bin\cygk5crypto-3.dll
         D:\cygwin64\bin\cygkrb5support-0.dll
           D:\cygwin64\bin\cygintl-8.dll
       D:\cygwin64\bin\cygkrb5-3.dll
         D:\cygwin64\bin\cygcom_err-2.dll
     D:\cygwin64\bin\cygidn2-0.dll
       D:\cygwin64\bin\cygunistring-2.dll
     D:\cygwin64\bin\cyglber-2-4-2.dll
     D:\cygwin64\bin\cygldap-2-4-2.dll
       D:\cygwin64\bin\cygsasl2-3.dll
       D:\cygwin64\bin\cygssl-1.1.dll
     D:\cygwin64\bin\cygnghttp2-14.dll
     D:\cygwin64\bin\cygpsl-5.dll
     D:\cygwin64\bin\cygssh2-1.dll
       D:\cygwin64\bin\cygcrypto-1.0.0.dll
   D:\cygwin64\bin\cygjsoncpp-24.dll
   D:\cygwin64\bin\cygrhash-0.dll
   D:\cygwin64\bin\cyguv-1.dll

Re: cmake suddenly stopped working

[Norton Allen]

On 11/18/2020 6:31 AM, Marco Atzeri via Cygwin wrote:
> On 18.11.2020 01:24, Norton Allen wrote:
>> Rolling back cmake from 3.17.3-2 to 3.14.5-1 seems to have resolved 
>> the problem.
>>
>> Any idea why no one else seems to be seeing this problem with 3.17.3-2?
>>
>
> I assume you had an incomplete upgrade.
>
> what is the output of "cygcheck cmake" ?

I rolled back forward to 3.17.3-2 and verified that 3.17.3-2 still shows 
the problem:

$ cygcheck cmake
Found: C:\cygwin64\bin\cmake.exe
C:\cygwin64\bin\cmake.exe
   C:\cygwin64\bin\cygwin1.dll
     C:\WINDOWS\system32\KERNEL32.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-rtlsupport-l1-1-0.dll
       C:\WINDOWS\system32\ntdll.dll
       C:\WINDOWS\system32\KERNELBASE.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-processthreads-l1-1-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-processthreads-l1-1-1.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-heap-l1-1-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-memory-l1-1-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-handle-l1-1-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-synch-l1-1-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-synch-l1-2-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-file-l1-1-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-file-l1-2-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-namedpipe-l1-1-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-datetime-l1-1-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-sysinfo-l1-1-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-timezone-l1-1-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-localization-l1-2-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-processenvironment-l1-1-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-string-l1-1-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-debug-l1-1-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-errorhandling-l1-1-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-util-l1-1-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-profile-l1-1-0.dll
       C:\Program Files\OpenJDK\jdk-13\bin\api-ms-win-core-file-l2-1-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-console-l1-1-0.dll
       C:\Program 
Files\OpenJDK\jdk-13\bin\api-ms-win-core-console-l1-2-0.dll
   C:\cygwin64\bin\cyggcc_s-seh-1.dll
   C:\cygwin64\bin\cygstdc++-6.dll
   C:\cygwin64\bin\cygarchive-13.dll
     C:\cygwin64\bin\cygbz2-1.dll
     C:\cygwin64\bin\cygiconv-2.dll
     C:\cygwin64\bin\cyglz4-1.dll
     C:\cygwin64\bin\cyglzma-5.dll
     C:\cygwin64\bin\cygnettle-6.dll
     C:\cygwin64\bin\cygxml2-2.dll
       C:\cygwin64\bin\cygz.dll
   C:\cygwin64\bin\cygcurl-4.dll
     C:\cygwin64\bin\cygbrotlidec-1.dll
       C:\cygwin64\bin\cygbrotlicommon-1.dll
     C:\cygwin64\bin\cygcrypto-1.1.dll
     C:\cygwin64\bin\cyggssapi_krb5-2.dll
       C:\cygwin64\bin\cygk5crypto-3.dll
         C:\cygwin64\bin\cygkrb5support-0.dll
           C:\cygwin64\bin\cygintl-8.dll
       C:\cygwin64\bin\cygkrb5-3.dll
         C:\cygwin64\bin\cygcom_err-2.dll
     C:\cygwin64\bin\cygidn2-0.dll
       C:\cygwin64\bin\cygunistring-2.dll
     C:\cygwin64\bin\cyglber-2-4-2.dll
     C:\cygwin64\bin\cygldap-2-4-2.dll
       C:\cygwin64\bin\cygcrypto-1.0.0.dll
       C:\cygwin64\bin\cygsasl2-3.dll
       C:\cygwin64\bin\cygssl-1.0.0.dll
     C:\cygwin64\bin\cygnghttp2-14.dll
     C:\cygwin64\bin\cygpsl-5.dll
     C:\cygwin64\bin\cygssh-4.dll
     C:\cygwin64\bin\cygssl-1.1.dll
   C:\cygwin64\bin\cygjsoncpp-24.dll
   C:\cygwin64\bin\cygrhash-0.dll
   C:\cygwin64\bin\cyguv-1.dll

Re: cmake suddenly stopped working

[Marco Atzeri]

On 18.11.2020 14:54, Norton Allen wrote:
> On 11/18/2020 6:31 AM, Marco Atzeri via Cygwin wrote:
>> On 18.11.2020 01:24, Norton Allen wrote:
>>> Rolling back cmake from 3.17.3-2 to 3.14.5-1 seems to have resolved 
>>> the problem.
>>>
>>> Any idea why no one else seems to be seeing this problem with 3.17.3-2?
>>>
>>
>> I assume you had an incomplete upgrade.
>>
>> what is the output of "cygcheck cmake" ?
> 
> I rolled back forward to 3.17.3-2 and verified that 3.17.3-2 still shows 
> the problem:
> 
> $ cygcheck cmake
> Found: C:\cygwin64\bin\cmake.exe

>        C:\Program 
> Files\OpenJDK\jdk-13\bin\api-ms-win-core-rtlsupport-l1-1-0.dll

this is strange

Can you try also
    strace -o cmake.out /usr/bin/cmake --version

I expect an error with a specific shared library

Re: cmake suddenly stopped working

[Norton Allen]

On 11/18/2020 10:33 AM, Marco Atzeri via Cygwin wrote:
> On 18.11.2020 14:54, Norton Allen wrote:
>> On 11/18/2020 6:31 AM, Marco Atzeri via Cygwin wrote:
>>> On 18.11.2020 01:24, Norton Allen wrote:
>>>> Rolling back cmake from 3.17.3-2 to 3.14.5-1 seems to have resolved 
>>>> the problem.
>>>>
>>>> Any idea why no one else seems to be seeing this problem with 
>>>> 3.17.3-2?
>>>>
>>>
>>> I assume you had an incomplete upgrade.
>>>
>>> what is the output of "cygcheck cmake" ?
>>
>> I rolled back forward to 3.17.3-2 and verified that 3.17.3-2 still 
>> shows the problem:
>>
>> $ cygcheck cmake
>> Found: C:\cygwin64\bin\cmake.exe
>
>>        C:\Program 
>> Files\OpenJDK\jdk-13\bin\api-ms-win-core-rtlsupport-l1-1-0.dll
>
> this is strange
>
> Can you try also
>    strace -o cmake.out /usr/bin/cmake --version
>
> I expect an error with a specific shared library 

Yes, earlier in the thread I reported running with strace and 
identifying a specific symbol that was missing, apparently from the 
stdc++ library:

> This seems to be the crux of it. That entry point is simply not in the 
> g++ shared library. I have not figured out why this cropped up today, 
> since it is not present in the current (10.2.0-1) or previous 
> (9.3.0-2) versions. I will trying going back to 7.4.0.1, but it's hard 
> to imagine it's been gone so long and I haven't seen the problem 
> before today.
>
>     nort@easwhlpt3425080 /usr/bin
>     $ strings cygstdc++-6.dll | grep 
> _ZNSt19basic_ostringstreamIcSt11char_traits
> _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEE3strERKSs
> _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEE4swapERS3_
>     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1EOS3_
> _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1ERKSsSt13_Ios_Openmode 
>
> _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1ESt13_Ios_Openmode
>     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC2EOS3_
> _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC2ERKSsSt13_Ios_Openmode 
>
> _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC2ESt13_Ios_Openmode
>     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEED0Ev
>     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEED1Ev
>     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEED2Ev
>     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEaSEOS3_
>
>     nort@easwhlpt3425080 /usr/bin
>     $ strings cmake.exe | grep 
> _ZNSt19basic_ostringstreamIcSt11char_traits
>     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev
>     _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEED1Ev

_ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev is the symbol 
that popped up in the strace error dialog.

Re: cmake suddenly stopped working

[Marco Atzeri]

On 18.11.2020 17:09, Norton Allen wrote:
> On 11/18/2020 10:33 AM, Marco Atzeri via Cygwin wrote:
>> On 18.11.2020 14:54, Norton Allen wrote:
>>> On 11/18/2020 6:31 AM, Marco Atzeri via Cygwin wrote:
>>>> On 18.11.2020 01:24, Norton Allen wrote:
>>>>> Rolling back cmake from 3.17.3-2 to 3.14.5-1 seems to have resolved 
>>>>> the problem.
>>>>>
>>>>> Any idea why no one else seems to be seeing this problem with 
>>>>> 3.17.3-2?
>>>>>
>>>>
>>>> I assume you had an incomplete upgrade.

> _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev is the symbol 
> that popped up in the strace error dialog.
> 

can you try to re-install libstdc++6 ?

$ cygcheck -f /usr/bin/cmake.exe
cmake-3.17.3-2

$ cygcheck -f /usr/bin/cygstdc++-6.dll
libstdc++6-10.2.0-1

$ objdump -x cygstdc++-6.dll | grep 
_ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev
         [3985] _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev

$ objdump -x cmake.exe | grep 
_ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev
         561e40   3969 
_ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev

Re: cmake suddenly stopped working

[Norton Allen]

On 11/18/2020 11:35 AM, Marco Atzeri via Cygwin wrote:
> can you try to re-install libstdc++6 ?
>
> $ cygcheck -f /usr/bin/cmake.exe
> cmake-3.17.3-2
>
> $ cygcheck -f /usr/bin/cygstdc++-6.dll
> libstdc++6-10.2.0-1

Hmm, here's a problem:

   $ cygcheck -f /usr/bin/cygstdc++-6.dll
   libstdc++6-7.4.0-1

This is after doing a reinstall selecting 10.2.0-1 (twice!). Setup 
thinks I have 10.2.0-1 installed (i.e. that's what is displayed as 
current in the GUI), but /etc/setup/installed.db says:

   $ grep stdc /etc/setup/installed.db
   libstdc++6 libstdc++6-7.4.0-1.tar.bz2 0

Hmmm. I've been using a scripted setup procedure that automatically 
downloads the setup program and then starts it with specific arguments. 
For some reason that did not do what I thought it was doing (or what 
*it* thought it was doing).

I did it manually, and low and behold, many packages needed to be updated.

And now everything seems to be behaving as it ought to.

Thanks all for all suggestions offered!